苏州大学2018届高考考前指导卷1(含答案)

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【高考模拟】江苏省苏州市2018届高三第一次模拟考试英语Word版含答案

【高考模拟】江苏省苏州市2018届高三第一次模拟考试英语Word版含答案

2018届高三年级第一次模拟考试(五)英语第一卷(选择题,共85分)第一部分听力理解(共两节,满分20分)第一节(共5小题;每小题1分,满分5分)听下面5段对话。

每段对话后有一个小题,从题中所给的A、B、C三个选项中选出最佳选项,并标在试卷的相应位置。

听完每段对话后,你都有10秒钟的时间来回答有关小题和阅读下一小题。

每段对话仅读一遍。

() 1. Where does the conversation probably take place?A. In a library.B. In a bank.C. In a street.() 2. What are the speakers likely to do tomorrow night?A. Watch a game.B. Finish a report.C. Pick up some food.() 3. What time is it when the conversation takes place?A. About 6:30.B. About 7:30.C. About 8:00.() 4. What is the man going to do?A. Attend the birthday party.B. Order a pizza and play some games.C. Hang out with Jenny.() 5. What does the man think of the movie?A. Terrible.B. Amazing.C. Amusing.第二节(共15小题;每小题1分,满分15分)听下面5段对话或独白。

每段对话或独白后有几个小题,从题中所给的A、B、C三个选项中选出最佳选项,并标在调研卷的相应位置。

听每段对话或独白前,你将有时间阅读各个小题,每小题5秒钟;听完后,各小题将给出5秒钟的作答时间。

每段对话或独白读两遍。

江苏省苏州2018届高考数学考前指导卷Word版含解斩

江苏省苏州2018届高考数学考前指导卷Word版含解斩

江苏省苏州2018届高考数学考前指导卷一、填空题:(本大题共14小题,每小题5分,共70分)1. 已知集合{}{}21,0,2,2,A B a =-=,若B A ⊆,则实数a 的值为 .2. 已知()()2210,i m i i -+=是虚数单位,则实数m 的值为 .3.一个总体分为A,B 两层,用分层抽样方法从总体中抽取一个容量为10的样本.已知B 层中每个个体抽到的概率都为112,则总体中的个数为 .4.已知双曲线()22210y x b b -=>则b = . 5.右图是一个算法的流程图,则输出k 的值是 .6.若{},0,1,2a b ∈,则函数()22f x ax x b =++有零点的概率为 .7.设实数,x y 满足约束条件236y x x y y x ≤⎧⎪+≥⎨⎪≥-⎩,则目标函数2z x y =+的最小值为 .8.《九章算术》商功章有题:一圆柱形谷仓,高1丈3尺133寸,容纳谷2000斛(1丈=10尺,1尺=10寸,斛为容积单位,1斛 1.62≈立方尺,3π≈),则圆柱底面周长约为 丈.9.等比数列{}n a 的前n 项和为n S ,公比1q ≠,若3232S S =,则q 的值为 . 10.已知圆()()22:116C x y a -+-=,若直线20ax y +-=与圆C 相交于A,B 两点,且CA CB ⊥,则实数a 的值为 . 11.设点()1,2A ,非零向量(),a m n =,若对于直线340x y +-=上任意一点P ,AP a ⋅恒为定值,则m n= . 12.已知0,0a b >>,且11121a b b +=++,则2a b +的最小值为 . 13.已知函数()2,0,0x x x e f x x x e ⎧+<⎪⎪=⎨⎪≥⎪⎩,若()()()()123123f x f x f x x x x ==<<,则()21f x x 的取值范围为 .14.在ABC ∆中,已知3sin 2sin C B =,点M,N 分别是边AC,AB 的中点,则BM CN的取值范围为 . 二、解答题:本大题共6小题,共90分.解答应写出必要的文字说明或推理、验算过程.15.(本题满分14分)已知函数()()21cos .f x x x =(1)求函数()f x 的定义域和最小正周期;(2)当0,2x π⎛⎫∈ ⎪⎝⎭时,求函数()f x 的值域.16.(本题满分14分)如图,在四棱锥S ABCD -中,四边形ABCD 为矩形,E 为SA 的中点,2,3,SB BC SC ==(1)求证://SC 平面BDE ;(2)求证:平面ABCD ⊥平面SAB .17.(本题满分14分)在平面直角坐标系xoy 中,已知点()2,1P 在椭圆()2222:10x y C a b a b +=>>上且离心率为2(1)求椭圆C 的方程;(2)不经过坐标原点O 的直线l 与椭圆C 交于A,B 两点(不与点P 重合),且线段AB 的中为D ,直线OD 的斜率为1,记直线PA ,PB 的斜率分别为12,k k ,求证:12k k ⋅为定值.18.(本题满分16分)如图,某地区有一块长方形植物园,8ABCD AB =(百米),4BC =(百米),植物园西侧有一块荒地,现计划利用该荒地扩大植物园面积,使得新的植物园为HBCEFG 满足下列要求:E 在CD 的延长线上,H 在BA 的延长线上,0.5DE =(百米),4AH =(百米),N 为AH 的中点,,FN AH EF ⊥为曲线段,它上面的任意一点到AD 与AH 的距离乘积为定值,,FG GH 均为线段,,0.5GH HA GH ⊥=(百米).(1)求四边形FGHN 的面积;(2)已知音乐广场M 在AB 上,2AM =(百米),若计划在EFG 的某一处P 开一个植物园大门,在原植物园ABCD 内选一点Q ,为中心建一个休息区,使得QM PM =,且90QMP ∠=,问点P 在何处,AQ 最小.19.(本题满分16分)已知函数()212ln x f x x +=,且方程()0f x m -=有两个相异实数根()1212,.x x x x >. (1)求函数()f x 的单调递增区间;(2)求实数m 的取值范围;(3)证明:2212122x x x x +>.20.(本题满分16分)已知数列{}n c 的前n 项和为n S ,满足()22.n n S n c =+(1)求1c 的值,并证明数列{}n c 是等差数列;(2)若2n n n c a =,且数列{}n a 的最大项为54. ①求数列{}n a 的通项公式;②若存在正整数x ,使,,m n k a a xa 成等差数列(),,,m n k m n k N *<<∈,则当()m n k T x a a xa =++取得最大值时,求x 的最小值.江苏省苏州2018届高考数学考前指导卷答案。

苏州大学2018届高考考前指导卷2(终稿)

苏州大学2018届高考考前指导卷2(终稿)

苏州大学2018届高考考前指导卷2一、填空题:本大题共14小题,每小题5分,共计70分.不需要写出解答过程,请把答案直接填在答题..卡相应位置上....... 1.设全集{|2,}U x x x =∈N ≥,集合2{|5,}A x x x =∈N ≥,则UA = ▲ .2.已知i 是虚数单位,复数(12i)(i)a -+是纯虚数,则实数a 的值为 ▲ . 3.利用计算机随机产生0~1之间的数a ,则事件“310a ->”发生的概率为 ▲ .4.某地区连续5天的最低气温(单位:C ︒)依次为8,4,1,0,2--,则该组数据的方差为 ▲ . 5.执行如图所示的伪代码,则输出的结果为 ▲ .6.若抛物线24x y =的弦AB 过焦点F ,且AB 的长为6,则弦AB 的中点M 的纵坐标为 ▲ .7.已知一个正方体的外接球体积为1V ,其内切球体积为2V ,则21V V的值为 ▲ .8.设S n 是等比数列{a n }的前n 项和,若满足a 4 + 3a 11= 0,则2114S S = ▲ . 9.已知0a >,函数2()()f x x x a =-和2()(1)g x x a x a =-+-+存在相同的极值点,则a = ▲ . 10. 在平面直角坐标系xOy 中,已知圆C :x 2+(y -1)2=4,若等边△PAB 的一边AB 为圆C 的一条弦,则PC 的最大值为 ▲ .11. 若cos 2cos()4ααπ=+,则tan()8απ+= ▲ .12. 已知0,0a b >>,则222a ba b b a+++的最大值为 ▲ . 13. 在ABC △中,90C =∠°,24AB BC ==,,M N 是边AB 上的两个动点,且1MN =,则CM CN ⋅的取值范围为 ▲ .14. 设函数()33,2,,x x x a f x x x a ⎧-<=⎨-⎩,≥若关于x 的不等式()4f x a >在实数集R 上有解,则实数a 的取值范围是 ▲ .二、解答题:本大题共6小题,共计90分.请在答题卡指定区域内........作答,解答时应写出必要的文字说明、证明过程或演算步骤. 15.(本小题满分14分)如图,在多面体ABCDE 中,∠ABD =60º,BD =2AB ,AB ∥CE ,AB ⊥CD , (1)求证://AB 平面CDE ; (2)求证:平面ABC ⊥平面ACD . 16.(本小题满分14分)在△ ABC 中,角A ,B ,C 所对的边分别为a ,b ,c ,已知60B =︒,8c =. (1)若点M 是线段BC 的中点, 3AMBM=,求b 的值; (2)若12b =,求△ ABC 的面积.C ABDE(第15题图)某校在圆心角为直角,半径为1km 的扇形区域内进行野外生存训练.如图所示,在相距1km 的A ,B 两个位置分别有300,100名学生,在道路OB 上设置集合地点D ,要求所有学生沿最短路径到D 点集合,记所有学生行进的总路程为S (km ). (1)设ADO θ∠=,写出S 关于θ的函数表达式; (2)当S 最小时,集合地点D 离点A 多远?18.(本小题满分16分)在平面直角坐标系xOy 中,椭圆2222:1(0)x y C a b a b+=>>的离心率为22,右准线方程为4x =,(,0)Q n 是椭圆C 的长轴上一点(Q 异于长轴端点),过点Q 的直线l 交椭圆于A ,B 两点. (1)求椭圆C 的标准方程;(2)①若2n =,求OA OB ⋅的最大值;②在x 轴上是否存在一点P ,使得PA PB ⋅为定值,若存在,求出点P ;若不存在,请说明理由.O yxBAQ BDOA(第17题图)(第18题图)已知数列{a n },{b n }满足:b n =a n +1-a n (n ∈N *). (1)若a 1=1,b n =n ,求数列{a n }的通项公式; (2)若b n +1b n -1=b n (n ≥2),且b 1=1,b 2=2.①记c n =a 6n -1(n ≥1),求证:数列{c n }为等差数列;②若数列{a nn}中任意一项的值均未在该数列中重复出现无数次,求首项a 1应满足的条件.20.(本小题满分16分)已知函数()ln f x x ,1()g x xx. (1)①若直线1ykx 与()ln f x x 的图像相切, 求实数k 的值;②令函数()()()h x f x g x ,求函数()h x 在区间[,1]a a上的最大值.(2)已知不等式2()()f x kg x 对任意的(1,)x 恒成立,求实数k 的范围.苏州大学2018届高考考前指导卷(2)参考答案一、填空题1.{2} 2.2- 3.234.16 5.11 6.2 7. 8.769.3 10.4 11.1312.2 13. 11[,9]4 14. 1(,)(7,)2-∞+∞填空题参考解答或提示 1.{}{|2}2UA x x x =<∈=N ≤.2. (12i)(i)(2)(12)i a a a -+=++-是纯虚数,所以实数a 的值为2-.3.本题为几何概型,因为13103a a ->⇒>,所以所求概率112313P -==. 4. 8(4)(1)0215x +-+-++==,所以该组数据的方差为52211()165i i s x x ==-=∑.5.第1次,33S I ==,;第2次,75S I ==,;第三次,117S I ==,. 6.设1122(,),(,)A x y B x y ,则126AB y y p =++=,所以1262222M y y y +-===. 7.设正方体棱长为a,则333311132224π214π2V R R V R R a ⎛⎫⎪⎛⎫ ⎪===== ⎪⎪⎝⎭ ⎪⎝⎭8.由题意得74430a a q +⋅=,又40a ≠,所以713q =-,321211421411()1731161()3S q S q ---===---. 9. 2322()()2+f x x x a x ax a x =-=-,所以22()34+(3)()f x x ax a x a x a '=-=--;由题意得132a a -=或12a a -=,又0,a >所以3a =. 10.由题意知,在PAC △中,由正弦定理可得,sin sin PC ACPAC APC=∠∠, 所以2sin 4sin sin30PC PAC PAC =∠=∠︒,所以当90PAC ∠=︒时,PC 的最大值为4. 11. cos 2cos(),cos()2cos()48888ααααπππππ=++-=++,所以3sin()sin cos()cos 8888ααππππ+=+所以11tan()833tan8απ+===π.12.设20,20m a b n b a =+>=+>,则22,33m n n ma b --==, 所以原式242222233222233333m n n mn m n m m n m n m n --=+=---⋅=-≤, 当且仅当233n mm n=即2n m =,也即3222b a +=时等号成立. 13.设MN 的中点为D ,则2221=()()4CM CN CD DM CD DN CD DM CD ⋅+⋅+=-=-, 故只需考虑||CD 的最大、最小值.如图,点D 在D 1及D 2处(1212AD CD AB =⊥,)分别取得最大、最小值.由222137,34CD CD ==,所以CM CN ⋅的取值范围为11[,9]4. 14.由题意知,max ()4f x a >①当0a <时,因为(0)0f =, max ()4f x a >显然成立;②当0a =时,()33,02,0,x x x f x x x ⎧-<=⎨-⎩,≥ max ()(1)204f x f a =-=>=,满足题意;③当0a >时,令332,x x -=解得121,2x x =-=,所以 i )当02a <<时,max max ()(1)24,f x f a =-=>解得102a <<; ii )当2a >时,3()3f x a a <-,由题意334a a a ->,解得7a >; 综上所述,实数a 的取值范围是1(,)(7,)2-∞+∞.二、解答题15. 证明(1)由题意AB ∥CE ,CE ⊂面CDE ,AB ⊄平面CDE ,所以//AB 平面CDE.(2)在△ABD 中,因为∠ABD =60º,BD =2AB ,所以︒⋅⋅-+=60cos 2222BD AB BD AB AD ,即223AB AD =, 因为222BD AD AB =+,所以AB AD ⊥, 又AB CD AD CD D ⊥=,,所以⊥AB 平面ACD , 又⊂AB 面ABC ,所以平面ABC ⊥平面ACD.16. 解(1)因为点M 是线段BC 的中点,3AMBM=,设BM x =,则3AM x =, 又60B =︒,8c =,在△ABM 中,由余弦定理得2236428cos60x x x =+-⨯︒, 解得4x =(负值舍去),则4BM =,8BC =. 所以△ ABC 中为正三角形,则8b =.(2)在△ ABC 中,由正弦定理sin sin b c B C =,得8sin 2sin 12c BC b===. 又b c >,所以B C >,则C为锐角,所以cos 3C =则()1sin sin sin cos cos sin 2A B C B C B C =+=++=, 所以△ ABC的面积1sin 4826S bc A ===17. 解(1)因为在△OAD 中,θ=∠ADO ,1OA =,所以由正弦定理可知1ππsin sin sin 33AD ODθθ==⎛⎫+ ⎪⎝⎭, 解得πsin 3sin AD OD θθ⎛⎫+ ⎪⎝⎭=,且π2π(,)33θ∈,故πsin 33001001001sin S AD BD θθ⎤⎛⎫+ ⎪⎥⎝⎭⎥=+=+-⎢⎥⎢⎥⎣⎦3cos 50sin θθ-=+,π2π(,)33θ∈, (2) 令3cos sin y θθ-=,则有23cos 1sin y θθ-+'= ,当1cos 3θ>时,0y '<; 当1cos 3θ<时,0y '>;可知,当且仅当1cos 3θ=时,y 有最小值22,当AD =时,此时总路程S有最小值50km .答:当集合点D 离出发点Akm时,总路程最短,其最短总路程为50km .18. 解(1)由2c e a ==,右准线方程为24a x c==,所以,a =2b =,即椭圆22:184x y C +=.(2)①由已知,(2,0)Q ,当直线AB 垂直于x 轴时,A,(2,B , 2OA OB ⋅=.当直线AB 不垂直于x 轴时,设直线AB :(2)y k x =-,代入22184x y +=得2222(12)8880k x k x k +-+-=,设11(,)A x y ,22(,)B x y ,212121212(2)(2)OA OB x x y y x x k x x ⋅=+=+--2221212(1)2()4k x x k x x k =+-++2222222(1)(88)8241212k k k k k k k +-=-⋅+++224812k k -=+210212k =-+<2. 所以,当直线AB 垂直于x 轴时,OA OB ⋅取到最大值2. ②设点(,0)P t ,11(,)PA x t y =-,22(,)PB x t y =-, 当直线AB 不垂直于y 轴时,设AB :x my n =+,代入22184x y +=得222(2)280m y mny n +++-=,12121212()()()()PA PB x t x t y y my n t my n t y y ⋅=--+=+-+-+221212(1)()()()m y y m n t y y n t =++-++-22222(8)(1)2()()2n m m n n t n t m -+--=+-+ 22222[82()]8()2m n n n t n n t m ---+-=+-+, 令2282()812n n n t n ----=得2384n t n+=, 当2384n t n +=时,2222222883894()()522416n n n PA PB n t n n n n --+⋅=+-=+-=+-.当直线AB 垂直于y 轴时,(A n ,(,B n ,238(,0)4n P n+ 2222238894()54216n n PA PB n n n n+-⋅=-+=+-.所以,在x 轴上存在点238(,0)4n P n +,使得PA PB ⋅为定值2294516n n+-.方法二 先利用直线l 垂直于x 轴和垂直于y 轴两种情况下PA PB ⋅的值不变,猜想点238(,0)4n P n+,然后再证明此时PA PB ⋅为定值2294516n n+-. 19. 解(1)当n ≥2时,有a n =a 1+(a 2-a 1)+(a 3-a 2)+…+(a n -a n -1)=a 1+b 1+b 2+…+b n -1=n 22-n2+1.又a 1=1也满足上式,所以数列{a n }的通项公式是a n =n 22-n2+1.(2)①因为对任意的n ∈N *,有b n +6=b n +5b n +4=1b n +3=b n +1b n +2=b n , 所以c n +1-c n =a 6n +5-a 6n -1=b 6n -1+b 6n +b 6n +1+b 6n +2+b 6n +3+b 6n +4=1+2+2+1+12+12=7.所以数列{c n }为等差数列.②设c n =a 6(n -1)+i (n ∈N *)(其中i 为常数且i ∈{1,2,3,4,5,6},所以c n +1-c n =a 6(n -1)+6+i -a 6(n -1)+i =b 6(n -1)+i +b 6(n -1)+i +1+b 6(n -1)+i +2+b 6(n -1)+i +3+b 6(n -1)+i +4+b 6(n -1)+i +5=7,即数列{a 6(n -1)+i }均为以7为公差的等差数列.设f k =a 6k +i 6k +i =a i +7k i +6k =76(i +6k )+a i -76i i +6k =76+a i -76ii +6k (其中n =6k +i ,k ≥0,i 为{1,2,3,4,5,6}中一个常数)当a i =76i 时,对任意的n =6k +i ,有a n n =76;当a i ≠76i 时,f k +1-f k =a i -76i i +6(k +1)-a i -76ii +6k =(a i -76i )-6[i +6(k +1)](i +6k ),①若a i >76i ,则对任意的k ∈N 有f k +1<f k ,所以数列{a 6k +i 6k +i }为递减数列;②若a i <76i ,则对任意的k ∈N 有f k +1>f k ,所以数列{a 6k +i 6k +i }为递增数列.综上所述,集合B ={76}∪{43}∪{12}∪{-13}∪{-16}={76,43,12,-13,-16}.当a 1∈B 时,数列{a nn}中必有某数重复出现无数次;当a 1 B 时,数列{a 6k +i6k +i }(i =1,2,3,4,5,6)均为单调数列,任意一个数在这6个数列中最多出现一次,所以数列{an n }任意一项的值均未在该数列中重复出现无数次.20. 解(1)设切点00(,)x y ,1()f x x. 所以000001ln 1x y x y kx k ,,,所以20x e ,21ke . (2)因为1()g x xx在(0,)上单调递增,且(1)0g .所以1ln ,01,1()()|()|ln ||1ln , 1.x x x xh x f x g x x xxxxx x当01x 时,1()ln h x x xx ,211()10h x xx , 当1x ≥时,1()ln h x xxx ,222111()10x x h x xx x ,所以()h x 在(0,1)上单调递增,在(1,)上单调递减,且max()(1)0h x h .当01a 时,max()(1)0h x h ;当1a ≥时,max1()()ln h x h a a aa.(3)令1()2ln ()F x x k x x ,(1,)x .所以222212()(1)kx xkF x k xxx .设2()2x kx xk ,①当0k 时,()0F x ,所以()F x 在(1,)上单调递增,又(1)0F ,所以不成立;②当0k 时,对称轴01x k , 当11k≤时,即1k ≥,(1)220k ≤,所以在(1,)上,()0x ,所以()0F x ,又(1)0F ,所以()0F x 恒成立;当11k时,即01k ,(1)220k,所以在(1,)上,由()0x ,0xx ,所以0(1,)xx ,()0x ,即()0F x ;0(,)xx ,()0x ,即()0F x ,所以max0()()(1)0F x F x F ,所以不满足()0F x 恒成立.综上可知:1k ≥.。

2018届高考模拟试卷一参考答案 .doc

2018届高考模拟试卷一参考答案 .doc

2018届高考模拟试卷一参考答案一、填空题(本大题共14小题,每小题5分,共70分.请把答案填写在答卷规定的横线上)1.22.四3.284.35.8π 6.a >2 7.6π 8.54 9.6π10.3π11.448 12.2 13.24 14.()5333, 二、解答题(本大题共6小题,共90分.解答时应写出文字说明、证明过程或演算步骤) 15.(本小题满分14分)如图,在几何体中,四边形ABCD 为菱形,对角线AC 与BD 的交点为O ,四边形DCEF 为梯形,EF ∥CD ,FB FD =.(1)若2CD EF =,求证:OE ∥平面ADF ; (2)求证:平面ACF ⊥平面ABCD .【解析】(Ⅰ)证明:取AD 的中点G ,连接OG 、FG ,因为O 为对角线AC 与BD 的交点,则O 为AC 中点, 所以OG ∥CD ,且12OG CD =. 又因为EF ∥CD ,且2CD EF =,所以OG ∥EF ,OG EF =,则四边形OGFE 为平行四边形,----------3分 所以OE ∥FG .又因为FG ⊂平面ADF ,OE ⊄平面ADF ,OE ∥FG ,所以OE ∥平面ADF ;-------------------------------------------------------------------6分(Ⅱ)证明:因为四边形ABCD 为菱形,所以OC BD ⊥,--------------------------7分又因为FB FD =,O 是BD 的中点,所以OF BD ⊥,------------------8分 又有OFOC O OF =⊂,平面ACF ,OC ⊂平面ACF ,所以BD ⊥平面ACF ,----------------------------------------------12分 又因为BD ⊂平面ABCD ,所以平面ACF ⊥平面ABCD .----------------------------------------14分16.(本小题满分14分)已知函数()2sin()cos 6f x x x π=-.(1)求函数()f x 的最大值和最小正周期;(2)设ABC ∆的角A B C ,,的对边分别为a b c ,,,且c =,1()2f C =,若sin 2sin B A =,求边a ,b 的值.【解析】(Ⅰ)因为)2()2sin()cos 612cos cos 22cos cos 1cos 2221sin(2)62f x x xx x x x x x x x x ππ=-=-=-+=-=---------------------------------------------------------------------4分当且仅当,3x k k Z ππ=+∈时,max 1()2f x =--------------------------------------6分 最小正周期分别为和22T ππ==.------------------------------------------------7分 (Ⅱ)因为11()sin(2)622f C C π=--=,即sin(2)16C π-=,因为0C π<<,所以 112666C πππ-<-<,于是262C ππ-=,即3C π=.------------------------------10分 因为sin 2sin B A =,由正弦定理得2b a =,-------------------------------------12分 由余弦定理得2222cos3c a b ab π=+-,即2212a b ab +-=,联立22212b aa b ab =⎧⎨+-=⎩,解得24a b =⎧⎨=⎩.-------------------------------------------14分17.(本小题满分14分) 在平面直角坐标系xOy 中,椭圆C :22221(0)x y a b a b+=>>在椭圆C 上.(1)求椭圆C 的方程;-(2)设P 为椭圆上第一象限内的点,点P 关于原点O 的对称点为A ,点P 关于x 轴的对称点为Q ,设PD PQ λ=,直线AD 与椭圆C 的另一个交点为B ,若PA ⊥PB ,求实数λ的值.【解析】17.解:(1)因为点222,在椭圆C 上,则222112a b+=,------------------------------1分 又椭圆C 的离心率为32,可得32ca,即32ca , 所以2222223124b acaa a ,代入上式,可得22221a a +=, 解得24a ,故22114ba .所以椭圆C 的方程为2214x y += ...............................................................................................5分 (2)设P (x 0,y 0),则A (-x 0,-y 0),Q (x 0,-y 0). 因为=λ,则(0,y D -y 0)=λ(0,-2y 0),故y D =(1-2λ)y 0.所以点D 的坐标为(x 0,(1-2λ)y 0). ................................................................................................. 7分 设B (x 1,y 1),221222101010222210101010114414PB BAx x y y y y y y k k x x x x x x x x ...............................9分 又0000121BA ADy y y k k x x x故001441PBBAx k k y .----------------------------------------------------------------------11分又PA ⊥PB ,且0PAx k y , D QBPxAOy第17题所以1PB PA k k ,即0000141x y x y ,解得34. 所以34.................................................................................................................................... 14分 18.(本小题满分16分) 一块圆柱形木料的底面半径为12cm ,高为32cm ,要将这块木料加工成一只毛笔筒,在木料一端正中间掏去一个小圆柱,使小圆柱与原木料同轴,并且掏取的圆柱体积是原木料体积的三分之一,设小圆柱底面半径为r cm ,高为h cm ,要求笔筒底面的厚度超过2cm . (1)求r 与h 的关系,并指出r 的取值范围;(2)笔筒成形后进行后续加工,要求笔筒上底圆环面、桶内侧面、外表侧面都喷上油漆,其中上底圆环面、外表侧面喷漆费用均为a (元/ cm 2),桶内侧面喷漆费用为2a (元/cm 2),而桶内底面铺贴金属薄片,其费用是7a (元/ cm 2)(其中a 为正常数). ①将笔筒的后续加工费用y (元)表示为r 的函数;②求出当r 取何值时,能使笔筒的后续加工费用y 最小,并求出y 的最小值.【解析】(Ⅰ)据题意,221(1232)3r h ππ=⋅⋅,所以23248h r ⨯=,----------------------3分 因为322h ->,所以30h <即2324830r ⨯<,解得r >----------------------------------------------------------5分 又012r <<,所以125r <<;----------------------------------------------------------6分 (Ⅱ)①据题意,笔筒的后续加工费用22272(2)(1221232)y a r a rh a r πππππ=++⋅-⋅+⋅⋅,整理得2226412763248641276y a r a rh a a r a r a rππππππ=++⨯⨯=+⋅+⨯ 232326(152)a r rπ⨯=++,定义域为;----------------------11分 ②由①知,33/22323286(2)12r y a r a r rππ⨯-=-=⋅,令/0y =得8(,12)5r =∈,由表知,当8r =时,y 取极小值即最小值2064a π.------------------------15分答:当8r cm =时,能使笔筒的后续加工费用y 最小,最小值为2064a π元.----16分19.(本小题满分16分)已知数列{}n a 中,首项11a =,2a a =,12()n n n a k a a ++=+对任意正整数n 都成立,数列{}n a 的前n 项和为n S .(1)若12k =,且18171S =,求实数a 的值; (2)是否存在实数k ,使数列{}n a 是公比不为1的等比数列,且任意相邻三项n a ,1n a +,2n a +按某顺序排列后成等差数列.若存在,求出所有的k 的值;若不存在,请说明理由;(3)若12k =-,求n S (用a ,n 表示). 【解析】(Ⅰ)当12k =时,由12()n n n a k a a ++=+得121()2n n n a a a ++=+,即211n n n n a a a a +++-=-,所以数列{}n a 为等差数列,--------------------1分 公差为211d a a a =-=-,数列{}n a 的前n 项和为(1)(1)2n n n S n a -=+⋅-,由18171S =得18(181)17118(1)2a -=+⋅-, 解得2a =;---------------------------------------------------------3分(Ⅱ)设数列{}n a 为等比数列,则其公比为21a q a a ==,1n n a a -=,1n n a a +=,12n n a a ++=. 1︒若1n a +为等差中项,则122n n n a a a ++=+即112n n n a a a -+=+,解得1a =,与已知不符,舍去; 2︒若n a 为等差中项,则122n n n a a a ++=+即112n n n a a a -+=+,即220a a +-=,解得2a =-或1a =(舍),此时由12()n n n a k a a ++=+得11()n n n a k aa -+=+即2(1)a k a =+,故2215a k a ==-+;3︒ 若2n a +为等差中项,则212n n n a a a ++=+即112n n n a a a +-=+,即2210a a --=,解得12a =-或1a =(舍),仿2︒得2215a k a ==-+.---------------------------------------------------8分 综上,满足要求的实数k 有且仅有一个,25k =-;---------------------------------9分(Ⅲ)当12k =-时,121()2n n n a a a ++=-+,所以211()n n n n a a a a ++++=-+,于是32n n a a +++=211()n n n n a a a a +++-+=+.----------------------------------------11分1︒ 当n 为偶数时,123456112(1)()()()()()22n n n n n a S a a a a a a a a a a -+=++++++++=+=; ---------------------------------------------------------------------------------13分2︒ 当n 为奇数时,1234511231()()()()2n n n n S a a a a a a a a a a --=+++++++=++ 11211[()]1(1)22n n a a a a --=+⋅-+=-+(2n ≥),当1n =时,也适合该式, 所以11(1),2(1),2n n a n S n a n -⎧-+⎪⎪=⎨+⎪⎪⎩为奇数为偶数.-----------------------------------------------16分20.(本小题满分16分)已知函数1()ln f x a x x=+(0a ≠). (1)求函数()f x 的单调区间;(2)若存在两条直线1y ax b =+,2y ax b =+(12b b ≠)都是曲线()y f x =的切线,求实数a 的取值范围;(3)若{}|()0(0,1)x f x ⊆≤,求实数a 的取值范围.【解析】(Ⅰ)/2211()a ax f x x x x-=-=(0x >). 当0a <时,/()0f x <,()f x 的递减区间为(0,)+∞;----------------------------1分 当0a >时,由/()0f x =得1x a=,列表得:所以,函数()f x 的递减区间为1(0,)a ,递增区间为1(,)a+∞;-----------------------4分 (Ⅱ)因为存在两条直线1y ax b =+、2y ax b =+(12b b ≠)都是曲线()y f x =的切线, 所以/()f x a =至少有两个不等的正根,-----------------------------------------------5分 令/21()ax f x a x-==,得210ax ax -+=,记其两个根为1x 、2x (12x x <), 则2124010a a x x a ⎧∆=->⎪⎨=>⎪⎩,解得4a >,------------------------------------------------------------------------------------7分 而当4a >时,曲线()y f x =在点11(,())x f x 、22(,())x f x 处的切线分别为11()y ax f x ax =+-、22()y ax f x ax =+-,设()()F x f x ax =-(0x >),由2//1222()()1()()a x x x x ax ax F x f x a x x----+-=-==知,当12x x x <<时,/()0F x >即()F x 在区间12[,]x x 上是单调函数,因此12()()F x F x ≠,所以11()y ax f x ax =+-、22()y ax f x ax =+-不重合,即1y ax b =+、2y ax b =+(12b b ≠)是曲线()y f x =的两条不同的切线,故4a >;----------------10分(Ⅲ)当0a <时,函数()f x 是(0,)+∞内的减函数,因为11111()ln()10aaaaf ea e e e---=+=-<,而1(0,1)ae-∉,不符合题意;----------------------------------------------------------12分当0a >时,由(Ⅰ)知()f x 的最小值为1()ln (1ln )f a a a a a a=-+=-.1︒若1()0f a>即0a e <<时,{}|()0(0,1)x f x φ≤=⊆,所以0a e <<符合题意;2︒若1()0f a =即a e =时,{}1|()0(0,1)x f x e ⎧⎫≤=⊆⎨⎬⎩⎭,所以a e =符合题意;3︒若1()0f a <即a e >时,101a <<,而(1)10f =>,函数()f x 在1(,)a+∞内递增,所以当1x ≥时,()0f x >,又因为()f x 的定义域为(0,)+∞,所以{}|()0(0,1)x f x ≤⊆,符合题意.综上,实数a 的取值范围为(0,)+∞.----------------------------------------------16分课题经济生活第六课《投资理财的选择》知识目标能力目标考点1、2:我国的商业银行及其主要业务+ 储蓄存款利息的计算方法考点3:储蓄、债券、股票、商业保险等投资理财方式重点难点比较储蓄、债券、股票、商业保险四种投资理财方式的异同(知道排序);分析不同的投资行为(把握投资原则)。

最新-2018年普通高等学校招生全国统一考试(江苏卷)预

最新-2018年普通高等学校招生全国统一考试(江苏卷)预

2018年普通高等学校招生全国统一考试(江苏卷)预测2物理第Ⅰ卷(选择题共38分)一、本题共6小题,每小题3分,共18分,在每小题给出的四个选项中只有一个选项是符合题目要求的,选对得3分,有选错或不答的得0分1.原子核自发地放出电子的现象称为β 衰变,开始时科学家曾认为β 衰变中只放出电子,即β 粒子,后来发现,这个过程中,除了放出电子以外,还放出一种叫作“反中微子”的粒子,反中微子不带电,与其他物质的相互作用极弱.下面关于β 衰变的说法中正确的是()A.静止的原子核发生β 衰变时β 粒子与衰变后的核的运动速度方向一定相反B.原子核发生β 衰变时放出的能量等于β 粒子与衰变后的核的动能之和C.原子核能发生β 衰发,说明原子核内含有电子D.发生β 衰变后的原子核的核子数不变但带电量增加2.人造地球卫星在科研、国防等方面起着不可替代的作用.只要发射的技术高,就能使人造地球卫星()A.在地球赤道面离地面任意高度的圆轨道上,并且相对于地面永远是静止的B.在与地球赤道共面的圆轨道上做匀速圆周运动,但相对地面不一定是静止C.有可能在地球任一纬度线所决定的平面内,绕地球做匀速圆周运动D.始终在某一经度圈所在的平面内运动,且轨道与该经度圈为同心圆,卫星相对地面静止3.在研究微型电动机的性能时,应用如图2所示的实验电路.当调节滑动变阻器R使电动机停止转动时,电流表和电压表的示数分别为0.50A和2.0V.重新调节R使电动机恢复正常运转,此时电流表和电压表的示数分别为2.0A和24.0V,则这台电动机正确运转时的输出功率为()图2A.32W B.44W C.47W D.48W4.在电视机的显像管中,电子束的扫描是用磁偏转技术实现的,其扫描原理如图3所示.圆形区域内的偏转磁场方向垂直于圆面,当不加磁场时,电子束将通过O点而打在屏幕的中心M点.为了使屏幕上出现一条以M点为中点的亮线PQ,偏转磁场的磁感应强度B随时间变化的规律应是图4中的()图3图45.如图5所示,一木块B 放在水平地面上,木块A 放在木板B 的上面,木块A 的右端通过轻质弹簧固定在竖直墙壁上.用力F 向左拉木板B ,使它们以速度v 运动,这时弹簧秤示数为F .下列说法中正确的是( )图5A .木板B 受到的滑动摩擦力的大小等于F B .地面受到的滑动摩擦力的大小等于FC .若木板以2v 的速度运动,木块A 受到的滑动摩擦力的大小等于2FD .若用力2F 拉木板B ,木块A 受到的滑动摩擦力的大小等于F6.如图5所示,荷质比为e /m 的电子,以速度0v 沿AB 边射入边长为a 的等边三角形的匀强磁场区域中,欲使电子从BC 边穿出,磁感应强度B 的取值为( )图5A .aemv B 03=B .ae mv B 02=C .aemv B 03<D .ae mv B 02<二、本题共5小题,每小题4分,共20分.在每小题给出的四个选项中,有多项是正确的,全部选对的得4分,选不全的得2分,有选错或不答的得0分.7、如图所示,电源电动势为E ,内阻为r .当开关S 闭合,滑动变阻器的滑片P 位于中点位置时,三个小灯泡L 1、L 2、L 3都正常发光,且亮度相同,则( ) A .三个灯泡的额定功率相同 B .三个灯泡的额定电压相同 C .三个灯泡的电阻按从大到小排列是L 1、L 3、L 1 D .当滑片P 稍微向左滑动,灯L 1和L 3变暗,灯L 2变亮8、如图所示电路为演示自感现象的实验电路. 若闭合开关s ,电流达到稳定后通过线圈L 的电流为I 1,通过小灯泡L 2的电流 为I 2,小灯泡L 2处于正常发光状态,则以下说法正确的是( ) A .s 闭合的瞬间,L 2灯缓慢变亮,L 1灯立即亮; B .s 闭合的瞬间,通过线圈L 的电流由零逐渐增大到I 1; C .s 断开的瞬间,小灯泡L 2中电流由I 1逐渐减为零,方向与I 2相反;D .s 断开的瞬间,小灯泡L 2中电流由I 2逐渐减为零,方向不变.9、如图所示,一细光束通过玻璃三棱镜折射后分成a 、b 、c 三束单色光,则这三种单色光( ) A 、频率关系是a v <b v <c vB 、在真空中的传播速度关系是a v <b v <c vC 、通过同一双缝产生的干涉条纹的间距a d <b d <c dD 、通过同一双缝产生的干涉条纹的间距a d >b d >c d10、如图所示,某人正通过定滑轮用不可伸长的轻质细绳将质量为m 的货物提升到高处。

推荐-苏大附中2018年高考模拟试卷 精品

推荐-苏大附中2018年高考模拟试卷 精品

苏大附中2018年高考模拟试卷数 学本试卷分第Ⅰ卷(选择题)和第Ⅱ卷(非选择题)两部分。

共150分,考试时间120分钟。

第Ⅰ卷(选择题 共60分)一、选择题:本大题共12小题,每小题5分,共60分。

在每小题给出的四个选项中,有且只有一项是符合题目要求的.请把所选项前的字母填在题后括号内. 1.已知集合A ={1,2},B ={x ︱ax+1=0},若A B =B ,则实数a 的值组成的集合是 ( )A .{1-,2}B .{1,21-}C .{0,—1,21-}D .{1-,21-}2.已知31)4sin(=-πα,)4cos(απ+的值等于 ( )A .322B .322-C .31- D .313. 有50件产品,编号为0,1,2,…,49,现从中抽取5件进行检验,用系统抽样法所抽样本的编号可以是 ( ) A .5,10,15,20,25 B .5,13,21,29,37 C .8,22,23,1,20 D . 0,10,20,30,404. 方程04)1(22=-+-+y x y x 表示的曲线是 ( )A .一直线与一圆B .一直线与一半圆C .两射线与一圆D .两射线与一半圆5. 已知()43+=x x f ,则()11+-x f 的表达式为 ( )A .34+xB .37-xC .131-xD .34-x6.设︱a x -︱<ε,︱a y -︱<ε,则下列不等式中必成立的是 ( ) A .︱y x +︱<ε B .︱y x -︱<ε C .︱y x -︱>2ε D .︱y x -︱<2ε 7.已知a ,b 为两条不同的直线,α,β为两个不同的平面,且a ⊥α,b ⊥β,则下列命题中的假命题是 A .若a ∥b ,则α∥β B .若α⊥β,则a ⊥b ( )C .若a 、b 相交,则α、β相交D .若α、β相交,则a 、b 相交8.某厂产值第二年比第一年增长p %,第三年比第二年增长q %,又这两年的平均增长率为s %,则s 与2qp +的大小关系是 ( )A .s >2qp + B .s =2qp + C .s ≥2qp + D .s ≤2qp + 9.设(1+x )3+(1+x )4+…+(1+x )50=a 0+a 1x+a 2x 2+…+a 50x 50,则a 3等于 ( )A .351CB .451CC .350CD .450C10.将五列车停在五条不同的轨道上,其中a 列车不停在第一轨道上,b 列车不停在第二轨道上,那么不同的停放方法有 ( ) A .120种 B .96种 C .78种 D .72种 11.已知向量=(2,0),向量OC =(2,2),向量CA =()ααsin 2,cos 2,则向量OA 与OB 的夹角的取值范围为 ( )A .⎥⎦⎤⎢⎣⎡4,0π B .⎥⎦⎤⎢⎣⎡125,4ππ C .⎥⎦⎤⎢⎣⎡2,125ππ D .⎥⎦⎤⎢⎣⎡125,12ππ12.设函数()xx x f ++=11,a ,b *R ∈,且a ≠b ,则下列关系式成立的是( )A .⎪⎭⎫⎝⎛+2b a f >()ab f>⎪⎭⎫ ⎝⎛+b a ab f 2B .⎪⎭⎫⎝⎛+2b a f >⎪⎭⎫ ⎝⎛+b a ab f 2>()ab fC . ()ab f>⎪⎭⎫ ⎝⎛+b a ab f 2>⎪⎭⎫ ⎝⎛+2b a f D .⎪⎭⎫ ⎝⎛+b a ab f 2>()ab f >⎪⎭⎫ ⎝⎛+2b a f第Ⅱ卷(非选择题 共90分)二、填空题:本大题共有4小题,每小题4分,共16分.把答案填在题中横线上.13.设p :x <2-或x >1,则使┐p 成立的一个必要不充分条件是 (只需写出一个条件即可) 14.设x 、y 、z 满足x+y+z =1及0≤x ≤1,0≤y ≤2,3y+z ≥2,则2x+6y+4z 的最大值为 . 15.若把一个函数f (x )的图像按=⎪⎭⎫ ⎝⎛--2,3π平移后得到函数y =cosx 的图像,则f (x )的解析式为 .16. 已知α,β是实数,给出四个论断:①︱α+β︱=︱α︱+︱β︱;②︱α—β︱≤︱α+β︱;③︱α︱>22,︱β︱>22;④︱α+β︱>5。

苏州大学高三高考考前指导卷数学试题

苏州大学高三高考考前指导卷数学试题

苏州大学2013届高考考前指导卷(1)一、填空题:本大题共14小题,每小题5分,共计70分.不需要写出解答过程,请把答案直接填在答题卡相应位置上......... 1.已知i 是虚数单位,复数z 的共轭复数为z -,若2z =z -+ 2 - 3i ,则z = .2.在平面直角坐标系xOy 中,已知3y x =是双曲线22221x y a b-=的一条渐近线方程,则此双曲线的离心率为 .3.如图是样本容量为200的频率分布直方图.根据此样本的频率分布直方图估计,样本数据落在[6,10)内的频数为________.4.函数22()(1)(1)x axf x x x +=+-为奇函数的充要条件是a = . 5.某团队有6人入住宾馆中的6个房间,其中的房号301与302对门,303与304对门,305与306对门,若每人随机地拿了这6个房间中的一把钥匙,则其中的甲、乙两人恰好对门的概率为_______.6.阅读如图所示的流程图,运行相应的程序,若输入x 的值为-4,则输出y 的值为________.7.底面边长为2,侧棱与底面成60︒的正四棱锥的侧面积为____.8.已知π()3sin(2)6f x x =-,若存在(0,π)α∈,使()()f x f x αα+=-对一切实数x 恒成立,则α= .9.在平面直角坐标系中,点A ,B ,C 的坐标分别为(0,1),(4,2),(2,6).如果P (x ,y )是△ABC 围成的区域(含边界)上的点,那么当ω = xy 取到最大值时,点P 的坐标是________.10.已知A = { (x ,y ) | x 2 + y 2 ≤4 },B = { (x ,y ) | (x - a )2 + (y - a )2≤2a 2,a ≠ 0 },则A ∩B 表示区域的面积的取值范围是___________.11.方程 |e 1|10x ax -++=有两个不同的解,则实数a 的取值范围是________.12.已知函数)(x f 是定义在正实数集上的单调函数,且满足对任意x > 0,都有[()ln ]1e f f x x -=+,则(1)f = ________.13.已知O 是△ABC 的外心,AB = 2a ,AC = 2a ,∠BAC = 120︒,若→AO = x →AB +y →AC ,则x +y 的最小值是 .14.记集合P = { 0,2,4,6,8 },Q = { m | m = 100a 1 +10a 2 + a 3,且a 1,a 2,a 3∈P },将集合Q 中的所有元素排成一个递增的数列,则此数列的第68项是_______.二、解答题:本大题共6小题,共计90分.请在答题卡指定区域内........作答,解答时应写出必要的文字说明、证明过程或演算步骤. 15.(本小题满分14分)在△ABC 中,角A ,B ,C 的对边分别为a ,b ,c .已知()3cos 16cos cos B C B C --=. (1)求cos A ;(2)若a = 3,△ABC的面积为b ,c .16.(本小题满分14分)在直三棱柱ABC - A 1B 1C 1中,AB = AC = AA 1 = 3a , BC = 2a ,D 是BC 的中点,E ,F 分别是A 1A ,C 1C 上一点, 且AE = CF = 2a .(1)求证:B 1F ⊥平面ADF ;(2)求三棱锥B 1 - ADF 的体积; (3)求证:BE ∥平面ADF .A F CBDC B 111E 1 1 1 A如图,某自来水公司要在公路两侧排水管,公路为东西方向,在路北侧沿直线AE 排水管1l ,在路南侧沿直线CF 排水管2l ,现要在矩形区域ABCD 内沿直线EF 将1l 与2l 接通.已知AB = 60 m ,BC = 80 m ,公路两侧排管费用为每米1万元,穿过公路的EF 部分的排管费用为每米2万元,设EF 与AB 所成角为α.矩形区域ABCD 内的排管费用为W .(1)求W 关于α的函数关系式; (2)求W 的最小值及相应的角α.18.(本小题满分16分)已知椭圆E :22221(0)x y a b a b+=>>,它的上顶点为A ,左、右焦点分别为12,F F ,直线AF 1,AF 2分别交椭圆于点B ,C .(1)求证直线BO 平分线段AC ;(2)设点P (m ,n )(m ,n 为常数)在直线BO 上且在椭圆外,过P 的动直线l 与椭圆交于两个不同点M ,N ,在线段MN 上取点Q ,满足MP MQPN QN=,试证明点Q 恒在一定直线上.l 2l 1数列{a n }满足:a 1 = 5,a n +1-a n = 2(a n +1+a n )+15*()n ∈N ,数列{b n }的前n 项和S n 满足:S n = 2(1-b n ).(1)证明:数列{a n +1-a n }是一个等差数列,并求出数列{a n }的通项公式; (2)求数列{b n }的通项公式,并求出数列{a n b n }的最大项.20.(本小题满分16分)已知三次函数f (x ) = 4x 3+ax 2+bx +c (a ,b ,c ∈R )(1)如果f (x )是奇函数,过点(2,10)作y = f (x )图象的切线l ,若这样的切线有三条,求实数b 的取值范围;(2)当-1≤x ≤1时有-1≤f (x )≤1,求a ,b ,c 的所有可能的取值.苏州大学2013届高考考前指导卷(1)参考答案1.2 - i 2.2 3.64 4.- 1 5.156.2 7. 8.π2 9.(0,2π) 10.(52,5)11.a <e - 12.e 13.2 14.464 15.解:(1)3(cos cos sin sin )16cos cos B C B C B C +-=,得3cos cos 3sin sin 1B C B C -=-.即3cos()1B C +=-,从而()1cos cos 3A B C =-+=. (2) 由于0πA <<,所以sin A =.又1sin 2ABC S bc A ∆==bc = 6.①由余弦定理2222cos a b c bc A =+-,得22b c +=13.② 由①②两式联立可得b = 2,c = 3或b = 3,c = 2. 16.(1)证明:∵AB = AC ,D 为BC 中点,∴AD ⊥BC .在直三棱柱ABC - A 1B 1C 1中,∵B 1B ⊥底面ABC ,AD ⊂底面ABC ,∴AD ⊥B 1B . ∵BC I B 1B = B ,∴AD ⊥平面B 1BCC 1.∵B 1F ⊂平面B 1BCC 1,∴AD ⊥B 1F .在矩形B 1BCC 1中,∵C 1F = CD = a ,B 1C 1 = CF = 2a , ∴Rt △DCF ≌ Rt △FC 1B 1.∴∠CFD = ∠C 1B 1F .∴∠B 1FD = 90°.∴B 1F ⊥FD . ∵AD I FD = D ,∴B 1F ⊥平面AFD . (2)∵B 1F ⊥平面AFD ,∴1113B ADF ADF V S B F -=⋅⋅△=11132AD DF B F ⨯⨯⨯⨯=(3)连EF ,EC ,设EC AF M =I ,连DM ,2AE CF a ==Q ,∴四边形AEFC 为矩形,M ∴为EC 中点.D Q 为BC 中点,//MD BE ∴.MD ⊂Q 平面ADF ,.BE ⊄平面ADF ,//BE ∴平面ADF17.解:(1)如图,过E 作EM BC ⊥,垂足为M ,由题意得4(0tan )3MEF αα∠=≤≤, 故有60tan MF α=,60cos EF α=,8060tan AE FC α+=-, 所以60(8060tan )12cos W αα=-⨯+⨯ A FCBDC B 111E1 1 1 AMsin 18060120cos cos ααα=-+ sin 28060cos αα-=-.(2)设sin 2()cos f ααα-=(其中00π40,tan )23ααα<=≤≤,则22cos cos (sin )(sin 2)12sin ()cos cos f αααααααα----'==. 令()0f α'=得12sin 0α-=,即1sin 2α=,得6πα=.列表所以当6α=时有max ()f α=min 80W =+答:排管的最小费用为80+6πα=.18.(1)由题意,c a =a =,22222b a c c =-=, 故椭圆方程为2222132x y c c+=,即2222360x y c +-=,其中)A ,1(,0)F c -,∴直线1AF ,此时直线1AF的方程为)y x c =+,联立2222360,),x y c y x c ⎧+-=⎪⎨=+⎪⎩得2230x cx +=,解得10x=(舍)和232x c =-,即3(,)22B c -,由对称性知3(,)22C c c . 直线BO 的方程为3y x =,线段AC 的中点坐标为3()44c , AC 的中点坐标3(,)44c 满足直线BO 的方程,即直线BO 平分线段AC . (2)设过P 的直线l 与椭圆交于两个不同点的坐标为1122(,),(,)M x y N x y ,点(,)Q x y ,则22211236x y c +=,22222236x y c +=.∵MP MQ PN QN =,∴设MP MQPN QNλ==,则,MP PN MQ QN λλ=-=u u u r u u u r u u u u r u u u r , 求得1212,11x x x x m x λλλλ-+==-+,1212,11y y y y n y λλλλ-+==-+,∴222222121222,11x x y y mx ny λλλλ--==--, ∴2222222222221212112222223323(23)23611x x y y x y x y mx ny c λλλλλ-+-+-++===--, 由于m ,n ,C 为常数,所以点Q 恒在直线22360mx ny c +-=上.19.解 (1)令n = 1得a 2-5 = 2(a 2+5)+15,解得a 2 = 12,由已知得 (a n +1-a n )2 = 2(a n +1+a n )+15 ① (a n +2-a n +1)2 = 2(a n +2+a n +1)+15 ②将②-①得(a n +2-a n )(a n +2-2a n +1+a n ) = 2(a n +2-a n ), 由于数列{a n }单调递增,所以a n +2-a n ≠0,于是 a n +2-2a n +1+a n = 2,即(a n +2-a n +1)-(a n +1-a n ) = 2, 所以{a n +1-a n }是首项为7,公差为2的等差数列,于是 a n +1-a n = 7+2(n -1) = 2n +5,所以a n = (a n -a n -1)+(a n -1-a n -2)+…+(a 2-a 1)+a 1= (2n +3)+(2n +1)+…+7+5 = n (n +4).(2)在 S n = 2(1-b n )中令n = 1得b 1 = 2(1-b 1),解得b 1 = 23,因为S n = 2(1-b n ),S n +1 = 2(1-b n +1),相减得b n +1 = -2b n +1+2b n ,即3b n +1 = 2b n ,所以{b n }是首项和公比均为23的等比数列,所以b n = (23)n .从而a n b n = n (n +4)(23)n .设数列{a n b n }的最大项为a k b k ,则有 k (k +4)(23)k ≥(k +1)(k +5)(23)k +1,且k (k +4)(23)k ≥(k -1)(k +3)(23)k -1,所以k 2≥10,且k 2-2k -9≤0,因为k 是自然数,解得k = 4.所以数列{a n b n }的最大项为a 4b 4 = 51281.20.解 (1) 因为f (x )是奇函数,所以由f (-x ) = -f (x )得a = c = 0, 设切点为P (t ,4t 3+bt ),则切线l 的方程为y -(4t 3+bt ) = (12t 2+b )(x -t ),由于切线l 过点(2,10),所以10-(4t 3+bt ) = (12t 2+b )(2-t ),整理得b = 4t 3-12t 2+5, 令g (t ) = 4t 3-12t 2+5-b ,则g ′(t ) = 12t 2-24t = 12t (t -2),所以g (t )在(-∞,0)上是增函数,在(0,2)上是减函数,在(2,+∞)上是增函数,要使切线l 有三条,当且仅当g (t ) = 0有三个实数根,g (t ) = 0有三个实数根当且仅当g (0)>0,且g (2)<0,解得-11<b <5.(2)由题意,当x = ±1,±12时,均有-1≤f (x )≤1,故 -1≤4+a +b +c ≤1, ① -1≤-4+a -b +c ≤1, 即-1≤4-a +b -c ≤1, ② -1≤12+a 4+b2+c ≤1, ③ -1≤-12+a 4-b2+c ≤1,即-1≤12-a 4+b2-c ≤1, ④①+②得-2≤8+2b ≤2,从而b ≤-3; ③+④得-2≤1+2b ≤2,从而b ≥-3.代入①②③④得a +c = 0,a4+c = 0,从而a = c = 0. 下面证明:f (x ) = 4x 3-3x 满足条件.事实上,f ′(x ) = 12x 2-3 = 3(2x +1)(2x -1),所以f (x )在(-1, -12)上单调递增,在(-12, 12)上单调递减,在(12,1)上单调递增,而f (-1) = -1,f (-12) = 1,f (12) = -1,f (1) = 1,所以当-1≤x ≤1时 f (x )满足-1≤f (x )≤1.。

苏州大学2019届高考考前指导卷

苏州大学2019届高考考前指导卷

2
42
在 Rt△BOM 中, OB 2 , BOM ,故 BM 2 tan( ) .
别是 B, P .设 POA ,公路 MB, MN 的总长为 f ( ) .
(1)求 f ( ) 关于 的函数关系式,并写出函数的定义域; B
M
(2)求 f ( ) 的最小值.
P
O
AN
(第 17 题图)
18.(本小题满分 16 分)
如图,在平面直角坐标系 xOy 中,离心率为 6 的椭圆 C : x2 y2 1(a b 0) 过点
(第 10 题图)
uur uur 12.过点 P(1,1) 作圆 C : (x t)2 ( y t 2)2 1(t R) 的切线,切点分别为 A, B ,则 PA PB
的最小值为 ▲ .
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▲. 4.下表是某同学五次数学附加题测试的得分情况,则这五次测试得分的方差为 ▲ .
次数 1 2 3 4 5
得分 33 30 27 29 31
5.运行右图所示的伪代码,则输出的结果为 ▲ . 6.设集合 B 是集合 A {1, 2,3, 4} 的子集,若记事件 M 为“集合 B 中的
元素之和为 5”,则事件 M 发生的概率为 ▲ . 7.设曲线 y x 1 在点(3,2)处的切线与直线 ax y 1 0 垂直,则实
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3 (1)求椭圆 C 的标准方程; (2) A, B 是椭圆的左右顶点, P, Q 是椭圆上与 A, B 不重合的两点,若满足 kAP 2kQB ,

高考数学试题-苏州大学2018届高考指导测试(二) 最新

高考数学试题-苏州大学2018届高考指导测试(二) 最新

苏州大学2018届高考指导测试 (二)高 三 数 学(正题) 2018. 5考生注意:1.本试卷共4页,包括(第1题—第12题)、(第13题—第17题)两部分。

本试卷满分150分,考试时间120分钟。

2.答将填空题答案和解答题的解答过程写在答题卷上,在本试卷上答题无效。

3.答题前,务必将自己的姓名、学校、准考证号写在答卷纸的规定位置。

一、填空题(本大题共14小题,每小题5分,共90分。

请把答案填写在答题卡相应位置上) 1. 若2(31)i 25i a a a -+-=+,其中i 是虚数单位,则实数a 的值为 ▲ .2. 在平面直角坐标系xOy 中,“方程22113x y k k +=--表示焦点在x 轴上的双曲线”的充要条件是“实数k ∈ ▲ ”.3. 某地区在连续7天中,新增某种流感的数据分别为4,2,1,0,0,0,0,则这组数据的方差s 2= ▲ .4. 已知角α是锐角,求sin α+3cos α的取值范围 ▲ .5. 设m ,n 是两条不同的直线,α,β,γ是两个不同的平面,有下列四个命题:①⎩⎨⎧α∥ββ∥γ⇒α∥γ; ②⎩⎨⎧α⊥βm ∥α⇒m ⊥β; ③⎩⎨⎧m ⊥αm ∥β⇒α⊥β; ④⎩⎨⎧m ∥n n ⊂α⇒m ∥α.其中真命题的是 ▲ (填上所有真命题的序号).6. 将A ,B ,C ,D 四个人平均分成两组,则“A ,B 两人恰好在同一组”的概率为 ▲ .7. 右图是一个算法的流程图,最后输出的n = ▲ .8. 设S n 表示等差数列{a n }的前n 项和,已知a 5=3a 3,则95S S = ▲ .9. 已知函数()f x 是定义在(0,)+∞上的单调增函数,当n *∈N 时,()f n *∈N ,若[()]3f f n n =,则f (5)的值等于 ▲ .10. 已知f (x )=x 3-3x ,过A (1,m )可作曲线y =f (x )的三条切线,则m 的取值范围是 ▲ .高三数学 第1页 共4页11. 已知D 是由不等式组⎩⎨⎧x -2y ≥0,x +3y ≥0所确定的平面区域,则圆x 2+y 2=4 围成的区域与区域D的公共部分的面积为 ▲ .12. 在平面直角坐标系xOy 中,设直线l :10kx y -+=与圆C :224x y +=相交于A 、B 两点,以OA ,OB 为邻边作□OAMB ,若点M 在圆C 上,则实数k = ▲ .13. 在正六边形ABCDEF 中,AB =1,AP xAB yAF =+,则x +y 的取值范围是 ▲ .14. 将所有3的幂,或者是若干个3的幂之和,由小到大依次排列成数列1,3,4,9,10,12,13,…,则此数列的 第100项为 ▲ .二、解答题(本大题共6小题,共90分.解答题应写出文字说明、证明过程或演算步骤) 15. (本小题满分14分) 已知向量m =(a ,cos2x ),n =(1+sin2x ,3),x ∈R ,记f (x )=m ⋅n .若y =f (x )的图象经过点( π4,2 ).(1)求实数a 的值;(2)设x ∈[-π4,π4],求f (x )的最大值和最小值;(3)将y =f (x )的图象向右平移π12,再将得到的图象上各点的横坐标伸长到原来的4倍,纵坐标不变,得到y =g (x )的图象,求y =g (x )的单调递减区间. 16.(本小题满分14分)在四棱锥P -ABCD 中,∠ABC =∠ACD =90°,∠BAC =∠CAD =60°, P A ⊥平面ABCD ,E 为PD 的中点,P A =2AB =2. (Ⅰ)求四棱锥P -ABCD 的体积V ;(Ⅱ)若F 为PC 的中点,求证PC ⊥平面AEF ; (Ⅲ)求证CE ∥平面P AB .FCPA BCDEF高三数学第2页共4页17.(本小题满分15分)某企业有两个生产车间分别在A,B两个位置,A车间有100名员工,B车间有400名员工,现要在公路AC上找一点D,修一条公路BD,并在D处建一个食堂,使得所有员工均在此食堂用餐,已知A,B,C中任意两点间的距离均有1km,设∠BDC=α,所有员工从车间到食堂步行的总路程为S.(1)写出S关于α的函数表达式,并指出α的取值范围;(2)问食堂D建在距离A多远时,可使总路程S最少?18.(本小题满分15分)已知椭圆C:x2a2+y2b2=1(a>b>0),直线l过点A(a,0)和B(0,b).(1)以AB为直径作圆M,连接MO并延长,与椭圆C的第三象限部分交于N,若直线NB是圆M的切线,求椭圆的离心率;(2)已知三点D(4,0),E(0,3),G(4,3),若圆M与△DEG恰有一个公共点,求椭圆方程.高三数学第3页共4页19.(本小题满分16分)已知数列{}na的前n项和nS满足:(1)1n naS aa=--(a为常数,且0,1a a≠≠).(1)求{}na的通项公式;(2)设21=+nnnSba,若数列{}n b为等比数列,求a的值;(3)在满足条件(2)的情形下,设111211nn nca a+=-++-(),数列{}nc的前n项和为T n.求证:13nT<.20.(本小题满分16分)已知关于x的函数f(x)=x2+2ax+b(其中a,b∈R).(1)求函数|f(x)|的单调区间;(2)对于一切a∈[0,1],若存在实数m,使得1|()|4f m≤与1|(1)|4f m+≤能同时成立,求b-a 的取值范围.高三数学 第4页 共4页苏州大学2018届高考指导测试 (二)1.2. 2. 3. 4.(1,2]4-2若函数tan y x ω=在区间π(,π)2上单调递增,则实数ω的取值范围是________.13(0,][1,]22⋃.5.①③6.137. 100. 8.275 9. 8 10.(-3,-2). 11.π2. 12. 0. 12-2在直角坐标平面内,点A (1,2)到直线l 的距离为1,且点B (4,1)到直线l 的距离为2,则这样的直线l 最多的条数为_________.4. 13.无13—2已知|a |=2,|b |=3,|c |=4,且a +b +c =0 ,则向量a 与b 的夹角的余弦值= .13-3在Rt △ABC 中,∠A =90°,AB =AC =2,点D 为AC 中点,点E 满足13BE BC =,则AE BD ⋅=__________.13-4设点O 为△ABC 的外心,AB =13,AC =12,则BC AO ⋅=_____. 14. 981. 二、解答题15. 16. 无17.(1)在△BCD 中,∵sin 60sin sin(120)BD BC CDαα==︒︒-,∴2sin BD α=,sin(120)sin CD αα︒-=.则sin(120)1sin AD αα︒-=-.S=sin(120)2400100[1]sin sin ααα︒-⋅+⋅-=cos 450sin αα--. 其中π3≤α≤2π3. (2)2sin sin (cos 4)cos sin S ααααα-⋅--'=-=214cos sin αα-. 令S '=0,得1cos 4α=. 当1cos 4α>时,S '<0,S 是α的单调减函数; 当1cos 4α<时,S '>0,S 是α的单调增函数. ∴当1cos 4α=时,S 取得最小值.此时,sin α=1sin sin(120)12211sin sin 2AD ααααα+︒-=-=-=-=11122-=-(答) 18已知椭圆C :x 2a 2+y 2b2=1(a >b >0),直线l 过点A (a ,0)和B (0,b ).(1)以AB 为直径作圆M ,连接MO 并延长,与椭圆C 的第三象限部分交于N ,若直线NB 是圆M 的切线,求椭圆的离心率; (2)已知三点D (4,0),E (0,3),G (4,3),若圆M与△CADEG 恰有一个公共点,求椭圆方程.数列问题19-1解 (1)11(1),1-=-aS a a ∴1,=a a 当2n ≥时,11,11n n n n n a aa S S a a a a --=-=---1nn a a a -=,即{}n a 是等比数列.∴1n n n a a a a -=⋅=; (2)由(1)知,2(1)(31)211(1)n n n n n aa a a a ab a a a ⋅----=+=-, 若{}n b 为等比数列,则有2213,b b b =而21232323223,,,a a a b b b a a +++=== 故22232322()3a a a a a +++=⋅, 解得13a =,再将13a =代入得3n n b =成立,所以13a =.(3)证明:由(2)知1()3n n a =,所以11111332111131311()1()33n n n n n n n c +++==+-+----+-1113131n n +=-+-,由111111,313313n n n n ++<>+-得111111,313133n n n n ++-<-+- 所以11133n n n c +-<,从而122231*********())33333333n n n n n T c c c ++=+++--++-=-<+(<13.函数问题20-1已知关于x 的函数f (x )=x 2+2ax +b (其中a ,b ∈R ). (1)求函数|f (x )|的单调区间;(2)对于一切a ∈[0,1],若存在实数m ,使得1|()|4f m ≤与1|(1)|4f m +≤能同时成立,求b -a的取值范围.。

苏州大学2018届高考考前指导卷2(终稿)

苏州大学2018届高考考前指导卷2(终稿)

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,求
的最大值;
②在 x轴上是否存在一点 P,使得
为定值,若存在,求出点 P;若不存在,请说明理由.
y
B
OQ
x
A
(第 18题图)
3
19.(本小题满分 16分) 已知数列{an},{bn}满足:bn=an+1-an(n∈N*).
(1)若 a1=1,bn=n,求数列{an}的通项公式;
(2)若 bn+1bn-1=bn(n≥2),且 b1=1,b2=2.
(1)若点 M 是线段 BC的中点,
,求 b的值;
(2)若
,求△ ABC的面积.

.
2
17.(本小题满分 14分) 某校在圆心角为直角,半径为
的扇形区域内进行野外生存训练.如图所示,在相距
的 A,B
两个位置分别有 300,100名学生,在道路 OB上设置集合地点 D,要求所有学生沿最短路径到 D点集
S← 2I+1 I← I+2 End While Print S (第 5题图)
为▲.
8.设 Sn是等比数列{an}的前 n项和,若满足 a4+3a11=0,则
▲.
9.已知
,函数

存在相同的极值点,则
▲.
10.在平面直角坐标系 xOy中,已知圆 C:x2+(y-1)2=4,若等边△PAB的一边 AB为圆 C的一条弦,
所以
平面 CDE.
(2)在△ABD中,因为∠ABD=60º,BD=2AB,
所以
,即

因为
,所以

,所以
平面 ACD,

面 ABC,所以平面 ABC⊥平面 ACD.
16.解(1)因为点 M 是线段 来自C的中点,,设,则

江苏省苏州大学高考数学考前指导卷试题(一)苏教版

江苏省苏州大学高考数学考前指导卷试题(一)苏教版

苏州大学2014届高考考前指导卷(1)一、填空题:本大题共14小题,每小题5分,共计70分.不需要写出解答过程,请把答案直接填在答题卡相应位置上......... 1.已知集合A ={x |x >5},集合B ={x |x <a },若A I B={x |5<x <6},则实数a 的值为 .2.设(1+2i)2=a +b i(,a b ∈R ),则ab = .3.若函数f (x )=sin(x +φ)(0<φ<π)是偶函数,则φ= .4.已知双曲线C :x 2a 2-y 2b2=1的焦距为10,点P (2,1)在C 的渐近线上,则C 的方程为 .5.从3位男生1位女生中任选两人,恰好是一男一女的概率是________.6.已知函数2()a y x a x=+∈R 在1x =处的切线与直线210x y -+=平行,则a =________. 7.图1是某学生的数学考试成绩茎叶图,第1次到第14次的考试成绩依次记为A 1,A 2,…,A 14.图2是统计茎叶图中成绩在一定范围内考试次数的一个算法流程图.那么算法流程图输出的结果是________.8.已知等差数列{a n }的公差不为零,a 1+a 2+a 5>13,且a 1,a 2,a 5成等比数列,则a 1的取值范围为 .9.在△ABC 中,若AB =1,3,||||AC AB AC BC =+=u u u r u u u r u u u r ,则BA →·BC →|BC →|= .10.在△ABC 中,角A ,B ,C 的对边分别是a ,b ,c ,a =8,b =10,△ABC 的面积为203,则△ABC 的最大角的正切值是________.11.已知三棱锥P ABC -的底面是边长为3的正三角形,其三条侧棱的长分别为3,4,5,则该三棱锥P ABC -的体积为 .12.已知函数f (x )=|x 2+2x -1|,若a <b <-1,且f (a )=f (b ),则ab +a +b 的取值范围是 .13.已知实数b a ,分别满足15323=+-a a a ,55323=+-b b b , 则b a +的值为 .14.已知A ,B ,C 是平面上任意三点,BC =a ,CA =b ,AB =c ,则y =ca +b +b c的最小值是 .二、解答题:本大题共6小题,共计90分.请在答题卡指定区域内........作答,解答时应写出必要的文字说明、证明过程或演算步骤.15.已知△ABC 中,角A ,B ,C 的对边分别为a ,b ,c ,且2a cos B =c cos B +b cos C .(1)求角B 的大小;(2)设向量m =(cos A ,cos 2A ),n =(12,-5),求当m·n 取最大值时,tan C 的值.16.如图,在四棱锥P - ABCD 中,已知AB =1,BC = 2,CD = 4,AB ∥CD ,BC ⊥CD ,平面PAB ⊥平面ABCD ,PA ⊥AB . (1)求证:BD ⊥平面PAC ;(2)已知点F 在棱PD 上,且PB ∥平面FAC ,求DF :FP .17.某创业投资公司拟投资开发某种新能源产品,估计能获得10万元到1 000万元的投资收益.现准备制定一个对科研课题组的奖励方案:资金y (单位:万元)随投资收益x (单位:万元)的增加而增加,且奖金不超过9万元,同时奖金不超过投资收益的20%. (1)若建立函数y =f (x )模型制定奖励方案,试用数学语言表述该公司对奖励函数f (x )模型的基本要求,并分析函数y =x150+2是否符合公司要求的奖励函数模型,并说明原因;A B C D F P(2)若该公司采用模型函数y =10x -3ax +2作为奖励函数模型,试确定最小的正整数a 的值.18.椭圆C :22221(0)x y a b a b+=>>的左、右焦点分别是12,F F ,离心率为32,过F 1且垂直于x 轴的直线被椭圆C 截得的线段长为1. (1)求椭圆C 的方程;(2)点P 是椭圆C 上除长轴、短轴端点外的任一点,过点P 作直线l ,使得l 与椭圆C 有且只有一个公共点,设l 与y 轴的交点为A ,过点P 作与l 垂直的直线m ,设m 与y 轴的交点为B ,求证:△PAB 的外接圆经过定点.19.已知函数f (x )=ax +ln x ,g (x )=e x.(1)当a ≤0时,求f (x )的单调区间;(2)若不等式g (x )<x -mx有解,求实数m 的取值范围.20.已知无穷数列{a n }的各项均为正整数,S n 为数列{a n }的前n 项和.(1)若数列{a n }是等差数列,且对任意正整数n 都有33()n n S S 成立,求数列{a n }的通项公式;(2)对任意正整数n ,从集合{a 1,a 2,…,a n }中不重复地任取若干个数,这些数之间经过加减运算后所得数的绝对值为互不相同的正整数,且这些正整数与a 1,a 2,…,a n 一起恰好是1至S n 全体正整数组成的集合. (ⅰ)求a 1,a 2的值;(ⅱ)求数列{a n }的通项公式.苏州大学2014届高考考前指导卷(1)参考答案一、填空题1.6 2.12 3.π2 4.x 220-y 25=1 5.126.07.108.(1, +∞) 9.12 10.533或- 3 11.1112.(-1,1) 13.214.2-12二、解答题15.(1)由题意,2sin A cos B =sin C cos B +cos C sin B ,所以2sin A cos B =sin(B +C )=sin(π-A )=sin A .因为0<A <π,所以sin A ≠0.所以cos B =22.因为0<B <π,所以B =π4. (2)因为m·n =12cos A -5cos 2A ,所以m·n =-10cos 2A +12cos A +5=-10⎝⎛⎭⎪⎫cos A -352+435.所以当cos A =35时,m·n 取最大值.此时sin A =45(0<A <π2),于是tan A =43.所以tan C =-tan(A +B )=-tan A +tan B1-tan A tan B=7.16.证明(1)∵平面PAB ⊥平面ABCD ,平面PAB I 平面ABCD = AB , PA ⊥AB ,PA ⊂平面PAB ,∴ PA ⊥平面ABCD .∵BD ⊂平面ABCD ,∴PA ⊥BD .连结AC BD O =I ,∵AB = 1,BC = 2,CD = 4, ∴12AB BC BC CD ==. ∵AB ∥CD ,BC ⊥CD ,∴Rt ABC ∆∽Rt BCD ∆. ∴BDC ACB ∠=∠.∴90ACB CBD BDC CBD ∠+∠=∠+∠=︒. 则AC ⊥BD .∵AC PA A =I ,∴BD ⊥平面PAC .(2)∵PB //平面FAC ,PB ⊂平面PBD ,平面PBD I 平面FAC= FO ,∴FO ∥PB ,∴DF DOPF OB=. 又∵AB //CD ,且14BO AB OD CD ==,∴DF :FP=4:1. 17.(1)设奖励函数模型为y =f (x ),按公司对函数模型的基本要求,函数y =f (x )满足:当x ∈[10,1 000]时,①f (x )在定义域[10,1 000]上是增函数;②f (x )≤9恒成立;③f (x )≤x5恒成立.对于函数模型f (x )=x150+2.当x ∈[10,1 000]时,f (x )是增函数,f (x )max =f (1 000)=1 000150+2=203+2<9,所以f (x )≤9恒成立.但x =10时,f (10)=115+2>105,即f (x )≤x5不恒成立,故该函数模型不符合公司要求.(2)对于函数模型f (x )=10x -3a x +2,即f (x )=10-3a +20x +2,当3a +20>0,即a >-203时递增;要使f (x )≤9对x ∈[10,1 000]恒成立,即f (1 000)≤9,3a +18≥1 000,a ≥9823;要使f (x )≤x 5对x ∈[10,1 000]恒成立,即10x -3a x +2≤x 5,x 2-48x +15a ≥0恒成立,所以a ≥1925.综上所述,a ≥9823,所以满足条件的最小的正整数a 的值为328.18.(1)由于c 2=a 2-b 2,将x =-c 代入椭圆方程22221x y a b +=,得y =±2b a .由题意知22b aP FDCBA O=1,即a =2b 2,又e =ca=32, 所以a =2,b =1. 所以椭圆C 的方程为2214x y +=.(2)设P (x 0,y 0)(y 0≠0),则直线l 的方程为y -y 0=k (x -x 0).联立0022,1,4y kx y kx x y =+-⎧⎪⎨+=⎪⎩ 整理得(1+4k 2)x 2+8(ky 0-k 2x 0)x +4(y 20-2kx 0y 0+k 2x 20-1)=0.由题意Δ=0,即(4-x 20)k 2+2x 0y 0k +1-y 20=0.又220014x y +=,所以16y 20k 2+8x 0y 0k +x 20=0,故k =-4x y . 所以直线l 方程为0014x xy y +=,令x =0,解得点A 01(0,)y ,又直线m 方程为00043y y x y x =-,令x=0,解得点B 0(0,3)y -, △PAB 的外接圆方程为以AB 为直径的圆方程,即2001()(3)0x y y y y +-+=.整理得:220013(3)0x y y y y +-+-=,分别令2230,0,x y y ⎧+-=⎨=⎩ 解得圆过定点(.19.(1)f (x )的定义域是(0,+∞),f ′(x )=a +1x(x >0),1°当a =0时,f ′(x )>0,∴f (x )在(0,+∞)上单调递增;2°当a <0时,由f ′(x )=0,解得x =-1a,则当x ∈⎝ ⎛⎭⎪⎫0,-1a 时,f ′(x )>0,f (x )单调递增,当x ∈⎝ ⎛⎭⎪⎫-1a ,+∞时,f ′(x )<0,f (x )单调递减,综上所述:当a =0时,f (x )在(0,+∞)上单调递增,当a <0时,f (x )在⎝ ⎛⎭⎪⎫0,-1a 上单调递增,在⎝ ⎛⎭⎪⎫-1a ,+∞上单调递减.(2)由题意:e x<x -m x有解,即e x x <x -m 有解,因此只需m <x -e xx ,x ∈(0,+∞)有解即可,设h (x )=x -e xx ,h ′(x )=1-e xx -ex2x=1-e x⎝ ⎛⎭⎪⎫x +12x ,因为x +12x≥212=2>1,且x ∈(0,+∞)时e x>1, 所以1-e x⎝⎛⎭⎪⎫x +12x <0,即h ′(x )<0.故h (x )在(0,+∞)上单调递减,∴h (x )<h (0)=0,故m <0.20.(1)设无穷等差数列{a n }的公差为d ,因为33()n n S S =对任意正整数n 都成立,所以分别取n =1,n =2时,则有:⎩⎪⎨⎪⎧a 1=a 31,8a 1+28d =2a 1+d 3.因为数列{a n }的各项均为正整数,所以d ≥0. 可得a 1=1,d =0或d =2.当a 1=1,d =0时,a n =1,33()n n S S =成立;当a 1=1,d =2时,S n =n 2,所以33()n n S S =.因此,共有2个无穷等差数列满足条件,通项公式为a n =1或a n =2n -1. (2)(ⅰ)记A n ={1,2,…,S n },显然a 1=S 1=1.对于S 2=a 1+a 2=1+a 2,有A 2={1,2,…,S n }={1,a 2,1+a 2,|1-a 2|}={1,2,3,4},故1+a 2=4,所以a 2=3. (ⅱ)由题意可知,集合{a 1,a 2,…,a n }按上述规则,共产生S n 个正整数.而集合{a 1,a 2,…,a n ,a n +1}按上述规则产生的S n +1个正整数中,除1,2,…,S n 这S n 个正整数外,还有a n +1,a n +1+i ,|a n +1-i |(i =1,2,…,S n ),共2S n +1个数. 所以,S n +1=S n +(2S n +1)=3S n +1.又S n +1+12=3⎝ ⎛⎭⎪⎫S n +12,所以S n =⎝⎛⎭⎪⎫S 1+12·13n --12=12·3n -12.当n ≥2时,a n =S n -S n -1=12·3n -12-⎝ ⎛⎭⎪⎫12·13n --12=13n -,而a 1=1也满足a n =13n -.所以,数列{a n }的通项公式是a n =13n -.。

江苏省苏州大学高三数学考前指导试题(含解析)

江苏省苏州大学高三数学考前指导试题(含解析)

2017年江苏省苏州大学高考数学考前指导试卷一、填空题:(本大题共14小题,每小题5分,共70分)1.已知集合A={﹣1,0,2},B={2,a2},若B⊆A,则实数a的值为.2.已知(2﹣i)(m+2i)=10,i是虚数单位,则实数m的值为.3.一个总体分为A,B两层,用分层抽样方法从总体中抽取一个容量为10的样本.已知B层中每个个体被抽到的概率都为,则总体中的个体数为.4.已知双曲线的离心率为,则b= .5.如图是一个算法流程图,则输出的k值是6.若a,b∈{0,1,2},则函数f(x)=ax2+2x+b有零点的概率为.7.设变量x,y满足约束条件,则目标函数z=2x+y的最小值为.8.《九章算术》商功章有题:一圆柱形谷仓,高1丈3尺寸,容纳谷2000斛(1丈=10尺,1尺=10寸,斛为容积单位,1斛≈1.62立方尺,π≈3),则圆柱底面周长约为丈.9.等比数列{a n}的前n项和为S n,公比q≠1,若,则q的值为.10.已知圆C:(x﹣1)2+(y﹣a)2=16,若直线ax+y﹣2=0与圆C相交于AB两点,且CA⊥CB,则实数a的值是.11.设点A(1,2),非零向量,若对于直线3x+y﹣4=0上任意一点P,恒为定值,则= .12.若a>0,b>0,且,则a+2b的最小值为.13.已知函数,若f(x1)=f(x2)=f(x3)(x1<x2<x3),则的取值范围为.14.在△ABC中,若3sinC=2sinB,点E,F分别是AC,AB的中点,则的取值范围为.二、解答题:本大题共6小题,共90分.解答应写出必要的文字说明或推理、验算过程.15.已知函数f(x)=(1+tanx)cos2x.(Ⅰ)求函数f(x)的定义域和最小正周期;(Ⅱ)当x∈(0,)时,求函数f(x)的值域.16.如图,在四棱锥S﹣ABCD中,四边形ABCD为矩形,E为SA的中点,SB=2,BC=3,.(Ⅰ)求证:SC∥平面BDE;(Ⅱ)求证:平面ABCD⊥平面SAB.17.在平面直角坐标系xoy中,已知点P(2,1)在椭圆C:上且离心率为.(1)求椭圆C的方程;(2)不经过坐标原点O的直线l与椭圆C交于A,B两点(不与点P重合),且线段AB的中为D,直线OD的斜率为1,记直线PA,PB的斜率分别为k1,k2,求证:k1•k2为定值.18.如图,某地区有一块长方形植物园ABCD,AB=8(百米),BC=4(百米),植物园西侧有一块荒地,现计划利用该荒地扩大植物园面积,使得新的植物园为HBCEFG满足下列要求:E在CD的延长线上,H在BA的延长线上,DE=0.5(百米),AH=4(百米),N为AH的中点,FN⊥AH,EF为曲线段,它上面的任意一点到AD与AH的距离乘积为定值,FG,GH均为线段,GH⊥HA,GH=0.5(百米).(1)求四边形FGHN的面积;(2)已知音乐广场M在AB上,AM=2(百米),若计划在EFG的某一处P开一个植物园大门,在原植物园ABCD内选一点Q,为中心建一个休息区,使得QM=PM,且∠QMP=90°,问点P在何处,AQ最小.19.已知函数f(x)=,且方程f(x)﹣m=0有两个相异实数根x1,x2(x1>x2).(1)求函数f(x)的单调递增区间;(2)求实数m的取值范围;(3)证明:x12x2+x1x22>2.20.已知数列{c n}的前n项和为S n,满足2S n=n(c n+2).(1)求c1的值,并证明数列{c n}是等差数列;(2)若,且数列{a n}的最大项为.①求数列{a n}的通项公式;②若存在正整数x,使a m,a n,xa k成等差数列(m<n<k,m,n,k∈N*),则当T(x)=a m+a n+xa k 取得最大值时,求x的最小值.2017年江苏省苏州大学高考数学考前指导试卷参考答案与试题解析一、填空题:(本大题共14小题,每小题5分,共70分)1.已知集合A={﹣1,0,2},B={2,a2},若B⊆A,则实数a的值为0 .【考点】18:集合的包含关系判断及应用.【分析】由B⊆A,可得a2=0,解得a.【解答】解:∵B⊆A,∴a2=0,解得a=0.故答案为:0.2.已知(2﹣i)(m+2i)=10,i是虚数单位,则实数m的值为 4 .【考点】A5:复数代数形式的乘除运算.【分析】利用复数的运算法则、复数相等即可得出.【解答】解:(2﹣i)(m+2i)=10,化为:2m﹣8+(4﹣m)i=0,∴2m﹣8=4﹣m=0,解得m=4.故答案为:4.3.一个总体分为A,B两层,用分层抽样方法从总体中抽取一个容量为10的样本.已知B层中每个个体被抽到的概率都为,则总体中的个体数为120 .【考点】B3:分层抽样方法;C7:等可能事件的概率.【分析】本题考查分层抽样,抽样过程中每个个体被抽到的可能性相同,这是解决一部分抽样问题的依据,样本容量、总体个数、每个个体被抽到的概率,这三者可以知二求一.【解答】解:∵B层中每个个体被抽到的概率都为,∴总体中每个个体被抽到的概率是,∴由分层抽样是等概率抽样得总体中的个体数为10÷=120故答案为:120.4.已知双曲线的离心率为,则b= .【考点】KC:双曲线的简单性质.【分析】利用双曲线的离心率列出关系式求解即可.【解答】解:双曲线,可得a=1,e=,可得c=,则b==.故答案为:.5.如图是一个算法流程图,则输出的k值是11【考点】EF:程序框图.【分析】先判断程序框图的结构为直到型循环结构,然后按照程序框图进行循环,直到满足条件时输出k的值即可.【解答】解:根据程序框图分析,本框图为直到型循环结构第1次循环:k=2 S=4﹣5=﹣1 k=﹣1第2次循环:S=1﹣5=﹣4 k=﹣4第3次循环:S=16﹣5=11 k=11第3次循环:S=121﹣5=106 满足条件S>100,跳出循环输出k的值为11.故答案为:11.6.若a,b∈{0,1,2},则函数f(x)=ax2+2x+b有零点的概率为.【考点】CB:古典概型及其概率计算公式.【分析】当函数f(x)=ax2+2x+b没有零点时,a≠0,且△=4﹣4ab<0,即ab>1,由此利用对立事件概率计算公式能求出函数f(x)=ax2+2x+b有零点的概率.【解答】解:a,b∈{0,1,2},当函数f(x)=ax2+2x+b没有零点时,a≠0,且△=4﹣4ab<0,即ab>1,∴(a,b)有三种情况:(1,2),(2,1),(2,2),基本事件总数n=3×3=9,∴函数f(x)=ax2+2x+b有零点的概率为p=1﹣.故答案为:.7.设变量x,y满足约束条件,则目标函数z=2x+y的最小值为 3 .【考点】7C:简单线性规划.【分析】先根据条件画出可行域,设z=2x+y,再利用几何意义求最值,将最小值转化为y轴上的截距,只需求出直线z=2x+y,过可行域内的点B(1,1)时的最小值,从而得到z最小值即可.【解答】解:设变量x、y满足约束条件,在坐标系中画出可行域△ABC,A(2,0),B(1,1),C(3,3),则目标函数z=2x+y的最小值为3.故答案为:3.8.《九章算术》商功章有题:一圆柱形谷仓,高1丈3尺寸,容纳谷2000斛(1丈=10尺,1尺=10寸,斛为容积单位,1斛≈1.62立方尺,π≈3),则圆柱底面周长约为 5.4 丈.【考点】L2:棱柱的结构特征.【分析】根据圆柱的体积和高计算出圆柱的底面半径,从而求出圆周的底面周长.【解答】解:由题意得,圆柱形谷仓底面半径为r尺,谷仓高h=尺.于是谷仓的体积V==2000×1.62.解得r≈9.∴圆柱圆的周面周长为2πr≈54尺.故答案为:5.4.9.等比数列{a n}的前n项和为S n,公比q≠1,若,则q的值为﹣.【考点】89:等比数列的前n项和.【分析】根据等比数列的前n项和公式,列方程求解即可.【解答】解:等比数列{a n}中,其前n项和为S n,公比q≠1,由得=,整理得2q2﹣q﹣1=0,即(q﹣1)(2q+1)=0,解得q=﹣或q=1(不合题意,舍去),所以q的值为﹣.故答案为:﹣.10.已知圆C:(x﹣1)2+(y﹣a)2=16,若直线ax+y﹣2=0与圆C相交于AB两点,且CA⊥CB,则实数a的值是﹣1 .【考点】J9:直线与圆的位置关系.【分析】求出圆C的圆心C(1,a),半径r=4,由直线ax+y﹣2=0与圆C相交于AB两点,且CA⊥CB,得到AB=4,由此利用圆心C(1,a)到直线AB的距离d==,能求出a.【解答】解:圆C:(x﹣1)2+(y﹣a)2=16的圆心C(1,a),半径r=4,∵直线ax+y﹣2=0与圆C相交于AB两点,且CA⊥CB,∴AB==4,∴圆心C(1,a)到直线AB的距离:d==,解得a=﹣1.故答案为:﹣1.11.设点A(1,2),非零向量,若对于直线3x+y﹣4=0上任意一点P,恒为定值,则= 3 .【考点】9R:平面向量数量积的运算.【分析】设点P(x,y),由点P为直线上的任意一点,表示出向量,由•恒为定值,求出m、n的关系,再计算.【解答】解:设点P(x,y),∵点P为直线3x+y﹣4=0上的任意一点,∴y=4﹣3x,∴=(x﹣1,2﹣3x);又非零向量=(m,n),∴•=m(x﹣1)+n(2﹣3x)=(m﹣3n)x+(2n﹣m),且恒为定值,∴m﹣3n=0,即m=3n;∴==3.故答案为:3.12.若a >0,b >0,且,则a+2b 的最小值为.【考点】7F :基本不等式.【分析】把a+2b 变形为a+2b=,再利用已知可得a+2b=,利用基本不等式即可得出.【解答】解:∵a >0,b >0,且,∴a+2b===﹣==.当且仅当,a >0,b >0,且,即,a=时取等号.∴a+2b 的最小值为.故答案为.13.已知函数,若f (x 1)=f (x 2)=f (x 3)(x 1<x 2<x 3),则的取值范围为 (﹣1,0) .【考点】5B:分段函数的应用.【分析】利用导数法,分析函数的单调性及极值,可得f(x1)=f(x2)=f(x3)∈(0,),即有﹣<x1<﹣,可得==1+,计算即可得到所求范围.【解答】解:函数,∴函数f′(x)=,故当x<0时,函数为增函数,且f(x)<,当0≤x<1时,函数为增函数,且0≤f(x)<,当x≥1时,函数为减函数,且0<f(x)≤,若f(x1)=f(x2)=f(x3)(x1<x2<x3),则f(x1)=f(x2)=f(x3)∈(0,),即﹣<x1<﹣,故==1+∈(﹣1,0),故答案为:(﹣1,0).14.在△ABC中,若3sinC=2sinB,点E,F分别是AC,AB的中点,则的取值范围为.【考点】HP:正弦定理.【分析】由已知及正弦定理得AC=AB,AE=AC,AF=,由余弦定理可求BE2=AB2﹣AB2cosA,CF2=AB2﹣AB2cosA,从而化简可得=,结合范围cosA ∈(﹣1,1),可求的取值范围.【解答】解:∵3sinC=2sinB ,可得:3AB=2AC ,即:AC=AB ,又∵点E ,F 分别是AC ,AB 的中点,∴AE=AC ,AF=,∴在△ABE 中,由余弦定理可得:BE 2=AB 2+AE 2﹣2AB•AEcosA=AB 2+(AB )2﹣2AB•AB•cosA=AB 2﹣AB 2cosA ,在△ACF 中,由余弦定理可得:CF 2=AF 2+AC 2﹣2AF•ACcosA=(AB )2+(AB )2﹣2•AB•AB•cosA=AB 2﹣AB 2cosA ,∴==,∵A ∈(0,π),∴cosA ∈(﹣1,1),可得:∈(,),∴可得: =∈.故答案为:.二、解答题:本大题共6小题,共90分.解答应写出必要的文字说明或推理、验算过程.15.已知函数f (x )=(1+tanx )cos 2x .(Ⅰ)求函数f (x )的定义域和最小正周期;(Ⅱ)当x∈(0,)时,求函数f(x)的值域.【考点】GL:三角函数中的恒等变换应用;H1:三角函数的周期性及其求法.【分析】(1)由二倍角公式和两角和的正弦公式对函数化简,利用周期公式求得函数的最小正周期.(2)根据x的范围确定2x+的范围,进而利用正弦函数的性质求得函数的值域.【解答】解:(Ⅰ)函数f(x)的定义域为{x|x≠+kπ,k∈Z},∵f(x)=(1+tanx)cos2x=cos2x+sinxcosx,=cos2x+sin2x+=sin(2x+)+,∴f(x)的最小正周期为T=π.(Ⅱ)∵x∈(0,),∴<2x+<,∴sin(2x+)∈(﹣,1],∴f(x)∈(0,],即当x∈(0,)时,求函数f(x)的值域为(0,].16.如图,在四棱锥S﹣ABCD中,四边形ABCD为矩形,E为SA的中点,SB=2,BC=3,.(Ⅰ)求证:SC∥平面BDE;(Ⅱ)求证:平面ABCD⊥平面SAB.【考点】LY:平面与平面垂直的判定;LS:直线与平面平行的判定.【分析】(Ⅰ)连接AC交BD于F,则F为AC中点,连接EF,可得EF∥SC,即SC∥平面BDE.(Ⅱ)由SB2+BC2=SC2,得BC⊥SB,又四边形ABCD为矩形,即BC⊥平面SAB,可证平面ABCD ⊥平面SAB.【解答】证明:(Ⅰ)连接AC交BD于F,则F为AC中点,连接EF,∵E为SA的中点,F为AC中点,∴EF∥SC,又EF⊂面BDE,SC⊄面BDE,∴SC∥平面BDE.(Ⅱ)∵SB=2,BC=3,,∴SB2+BC2=SC2,∴BC⊥SB,又四边形ABCD为矩形,∴BC⊥AB,又AB、SB在平面SAB内且相交,∴BC⊥平面SAB,又BC⊂平面ABCD,∴平面ABCD⊥平面SAB.17.在平面直角坐标系xoy中,已知点P(2,1)在椭圆C:上且离心率为.(1)求椭圆C的方程;(2)不经过坐标原点O的直线l与椭圆C交于A,B两点(不与点P重合),且线段AB的中为D,直线OD的斜率为1,记直线PA,PB的斜率分别为k1,k2,求证:k1•k2为定值.【考点】KH:直线与圆锥曲线的综合问题;K4:椭圆的简单性质;KL:直线与椭圆的位置关系.【分析】(1)根据椭圆的离心率公式,将P代入椭圆方程,即可求得a和b的值,求得椭圆方程;(2)根据中点坐标公式及直线斜率公式,求得x1+x2=y1+y2,利用点差法求得直线l的斜率,将直线方程代入椭圆方程,利用韦达定理及直线的斜率公式,即可求得k1•k2为定值.【解答】解:(1)由椭圆的离心率e===,则a2=2b2,由P(2,1)在椭圆上,则,解得:b2=3,则a2=6,∴椭圆的标准方程:;(2)证明:设A(x1,y1),B(x2,y2),则D(,),由直线的斜率为1,则x1+x2=y1+y2,由点A,B在椭圆上,则,,两式相减整理得:,x1﹣x2+2(y1﹣y2)=0,则=﹣,设直线l的方程y=﹣x+t,,整理得:3x2﹣4tx+4t2﹣12=0,则x1+x2=,x1x2=,则k1•k2==,===,∴k1•k2为定值.18.如图,某地区有一块长方形植物园ABCD,AB=8(百米),BC=4(百米),植物园西侧有一块荒地,现计划利用该荒地扩大植物园面积,使得新的植物园为HBCEFG满足下列要求:E在CD的延长线上,H在BA的延长线上,DE=0.5(百米),AH=4(百米),N为AH的中点,FN⊥AH,EF为曲线段,它上面的任意一点到AD与AH的距离乘积为定值,FG,GH均为线段,GH⊥HA,GH=0.5(百米).(1)求四边形FGHN的面积;(2)已知音乐广场M在AB上,AM=2(百米),若计划在EFG的某一处P开一个植物园大门,在原植物园ABCD内选一点Q,为中心建一个休息区,使得QM=PM,且∠QMP=90°,问点P在何处,AQ最小.【考点】5C:根据实际问题选择函数类型.【分析】(1)建立坐标系,根据E点坐标得出曲线EF的方程,从而得出F点坐标,代入梯形的面积公式即可;(2)设P(x,y),用x,y表示出,,根据Q点位置求出x的范围得出P在曲线EF上,利用距离公式和基本不等式的性质得出AQ最小时的x的值即可得出P点位置.【解答】解:(1)以A为原点,以AB,AD所在直线为坐标轴建立平面直角坐标系xOy,如图所示:则E(﹣,4),∴曲线EF的方程为y=﹣,∴F(﹣2,1),N(﹣2,0),H(﹣4,0),G(﹣4,),∴FN=1,GH=,HN=2,∴四边形FGHN的面积为S==(平方百米).(2)设P(x,y),则=(x﹣2,y),=(y,2﹣x),=(2+y,2﹣x),∴,解得﹣2≤x≤2,∴P点在曲线EF上,﹣2≤x≤﹣,∴y=﹣,∴|AQ|=====﹣x﹣+2≥2+2,当且仅当﹣x=即x=﹣时取等号.∴当P为(﹣,﹣)时,|AQ|最小.19.已知函数f(x)=,且方程f(x)﹣m=0有两个相异实数根x1,x2(x1>x2).(1)求函数f(x)的单调递增区间;(2)求实数m的取值范围;(3)证明:x12x2+x1x22>2.【考点】6B:利用导数研究函数的单调性;6K:导数在最大值、最小值问题中的应用.【分析】(1)求出函数的导数,解关于导函数的不等式,求出函数的递增区间即可;(2)根据函数的单调性求出f(x)的最大值,通过讨论m的范围,结合函数的单调性判断出方程f(x)﹣m=0有两个相异实数根的m的范围即可;(3)由f(x1)=f(x2),得=,令x1=x2t,∵x1>x2,∴t>1,问题转化为证明lnt﹣1>0,即证lnt﹣>0,(*),令g(t)=lnt﹣,根据函数的单调性证明即可.【解答】解:(1)函数f(x)的定义域是(0,+∞),f′(x)=,令f′(x)>0,解得:0<x<1,故f(x)在(0,1)递增;(2)由(1),令f′(x)<0,解得:x>1,故f(x)在(0,1)递增,在(1,+∞)递减,故f(x)max=f(1)=1,①m>1时,f(x)=m无解,②m=1时,f(x)=1有1个解,③m≤0,x∈(1,+∞)时,f(x)>0,f(x)=m无解,x∈(0,1)时,f(x)递增,f(x)=m至多1个解,故x∈(0,+∞)时,f(x)=m至多1个解,④0<m<1时,x∈(0,1)时,f(x)递增,f()=0,f(1)=1,f(x)的图象不间断,f()<m<f(1),f(x)=m在(,1)内有1个解,即在(0,1)内有1个解,x∈(1,+∞)时,f(x)是减函数,先证明lnx≤x,令g(x)=lnx﹣x,则g′(x)=,令g′(x)>0,解得:0<x<e,令g′(x)<0,解得:x>e,故g(x)在(0,e)递增,在(e,+∞)递减,故g(x)max=g(e)=0,故lnx≤x,x∈(1,+∞)时,f(x)=≤<<=,令=m,即x=时,f()<m,又m<f(1),f(x)在(1,+∞)递减,故f(x)=m在(1,)内有1解,即在(1,+∞)内有1解,综上,当且仅当0<m<1时,f(x)=m在(0,+∞)内有2解,实数m的范围是(0,1);(3)由f(x1)=f(x2),得=,令x1=x2t,∵x1>x2,∴t>1,=1+2lnx2,则lnx2=lnt﹣,下面证明x1x2>1,∵lnx1+lnx2=2lnx2+lnt=lnt﹣1,故只需证明lnt﹣1>0,即证lnt﹣>0,(*),令g(t)=lnt﹣,∵g′(t)=>0,∴g(t)在(1,+∞)递增,g(t)在(0,+∞)上的图象不间断,则g(t)>g(1)=0,(*)成立,故x1x2>1,由基本不等式得x1+x2>2>2,故x12x2+x1x22>2.20.已知数列{c n}的前n项和为S n,满足2S n=n(c n+2).(1)求c1的值,并证明数列{c n}是等差数列;(2)若,且数列{a n}的最大项为.①求数列{a n}的通项公式;②若存在正整数x,使a m,a n,xa k成等差数列(m<n<k,m,n,k∈N*),则当T(x)=a m+a n+xa k 取得最大值时,求x的最小值.【考点】8H:数列递推式;8E:数列的求和.【分析】(1)2S n=n(c n+2),2S1=2c1=c1+2,解得c1=2,n≥2时,2c n=2S n﹣2S n﹣1.化为:(n﹣2)c n﹣(n﹣1)c n﹣1+2=0.可得(n﹣1)c n+1﹣nc n+2=0,相减可得:2c n=c n+1+c n﹣1.即可证明.(2)①设数列{c n}的公差为d,则a n=.对d分类讨论,d≤0时舍去,d>0,a n+1﹣a n=<0,在n≥2时恒成立,可得a2为最大值.由a2==,解得d.可得a n.②存在正整数x,使a m,a n,xa k成等差数列(m<n<k,m,n,k∈N*),可得2a n=a m+xa k,T(x)=a m+a n+xa k=3a n,由①可知:a2最大,首先考察a2.此时xa k=2a2﹣a1.即=,解得x=(k≥3).利用其单调性即可得出.【解答】解:(1)∵2S n=n(c n+2),∴2S1=2c1=c1+2,解得c1=2,n≥2时,2c n=2S n﹣2S n﹣1=n(c n+2)﹣(n﹣1)(c n﹣1+2).化为:(n﹣2)c n﹣(n﹣1)c n﹣1+2=0.∴(n﹣1)c n+1﹣nc n+2=0,相减可得:2c n=c n+1+c n﹣1.∴数列{c n}是等差数列,首项为2.(2)①设数列{c n}的公差为d,则a n=.若d≤0,则a n=≤a1=1,与已知数列{a n}的最大项为矛盾.若d>0,a n+1﹣a n=﹣=<0,在n≥2时恒成立,可得a2为最大值.由a2==,解得d=3.∴a n=.②∵存在正整数x,使a m,a n,xa k成等差数列(m<n<k,m,n,k∈N*),∴2a n=a m+xa k,T(x)=a m+a n+xa k=3a n,由①可知:a2最大,首先考察a2.此时xa k=2a2﹣a1=﹣1=.即=,解得x=(k≥3).考察3k﹣1=8,11,14,17,….当k=11时,x取得最小值,x==96∈N*.∴当T(x)=a m+a n+xa k取得最大值时,x的最小值为96.- 21 -。

苏州大学2013届高考考前指导卷(1)

苏州大学2013届高考考前指导卷(1)

苏州大学2013届高考考前指导卷(1)一、填空题:本大题共14小题,每小题5分,共计70分.不需要写出解答过程,请把答案直接填在答题卡相应位置上......... 1.已知i 是虚数单位,复数z 的共轭复数为z -,若2z =z -+ 2 - 3i ,则z = .2.在平面直角坐标系xOy 中,已知y 是双曲线22221x y a b-=的一条渐近线方程,则此双曲线的离心率为 .3.如图是样本容量为200的频率分布直方图.根据此样本的频率分布直方图估计,样本数据落在[6,10)内的频数为________.4.函数22()(1)(1)x axf x x x +=+-为奇函数的充要条件是a = . 5.某团队有6人入住宾馆中的6个房间,其中的房号301与302对门,303与304对门,305与306对门,若每人随机地拿了这6个房间中的一把钥匙,则其中的甲、乙两人恰好对门的概率为_______.6.阅读如图所示的流程图,运行相应的程序,若输入x 的值为-4,则输出y 的值为________.7.底面边长为2,侧棱与底面成60︒的正四棱锥的侧面积为____.8.已知π()3sin(2)6f x x =-,若存在(0,π)α∈,使()()f x f x αα+=-对一切实数x 恒成立,则α= .9.在平面直角坐标系中,点A ,B ,C 的坐标分别为(0,1),(4,2),(2,6).如果P (x ,y )是△ABC 围成的区域(含边界)上的点,那么当ω = xy 取到最大值时,点P 的坐标是________.10.已知A = { (x ,y ) | x 2 + y 2 ≤4 },B = { (x ,y ) | (x - a )2 + (y - a )2≤2a 2,a ≠ 0 },则A ∩B 表示区域的面积的取值范围是___________.11.方程 |e 1|10x ax -++=有两个不同的解,则实数a 的取值范围是________.12.已知函数)(x f 是定义在正实数集上的单调函数,且满足对任意x > 0,都有[()ln ]1e f f x x -=+,则(1)f = ________.13.已知O 是△ABC 的外心,AB = 2a ,AC = 2a ,∠BAC = 120︒,若→AO = x →AB +y →AC ,则x +y的最小值是 .14.记集合P = { 0,2,4,6,8 },Q = { m | m = 100a 1 +10a 2 + a 3,且a 1,a 2,a 3∈P },将集合Q中的所有元素排成一个递增的数列,则此数列的第68项是_______.二、解答题:本大题共6小题,共计90分.请在答题卡指定区域内........作答,解答时应写出必要的文字说明、证明过程或演算步骤. 15.(本小题满分14分)在△ABC 中,角A ,B ,C 的对边分别为a ,b ,c .已知()3cos 16cos cos B C B C --=. (1)求cos A ;(2)若a = 3,△ABC 的面积为b ,c .16.(本小题满分14分)在直三棱柱ABC - A 1B 1C 1中,AB = AC = AA 1 = 3a , BC = 2a ,D 是BC 的中点,E ,F 分别是A 1A ,C 1C 上一点, 且AE = CF = 2a .(1)求证:B 1F ⊥平面ADF ;(2)求三棱锥B 1 - ADF 的体积; (3)求证:BE ∥平面ADF .如图,某自来水公司要在公路两侧排水管,公路为东西方向,在路北侧沿直线AE 排水管1l ,在路南侧沿直线CF 排水管2l ,现要在矩形区域ABCD 内沿直线EF 将1l 与2l 接通.已知AB = 60 m ,BC = 80 m ,公路两侧排管费用为每米1万元,穿过公路的EF 部分的排管费用为每米2万元,设EF 与AB 所成角为α.矩形区域ABCD 内的排管费用为W .(1)求W 关于α的函数关系式; (2)求W 的最小值及相应的角α.18.(本小题满分16分)已知椭圆E :22221(0)x y a b a b +=>>的离心率为3,它的上顶点为A ,左、右焦点分别为12,F F ,直线AF 1,AF 2分别交椭圆于点B ,C .(1)求证直线BO 平分线段AC ;(2)设点P (m ,n )(m ,n 为常数)在直线BO 上且在椭圆外,过P 的动直线l 与椭圆交于两个不同点M ,N ,在线段MN 上取点Q ,满足MP MQPN QN=,试证明点Q 恒在一定直线上.数列{a n }满足:a 1 = 5,a n +1-a n = 2(a n +1+a n )+15*()n ∈N ,数列{b n }的前n 项和S n 满足:S n = 2(1-b n ).(1)证明:数列{a n +1-a n }是一个等差数列,并求出数列{a n }的通项公式; (2)求数列{b n }的通项公式,并求出数列{a n b n }的最大项.20.(本小题满分16分)已知三次函数f (x ) = 4x 3+ax 2+bx +c (a ,b ,c ∈R )(1)如果f (x )是奇函数,过点(2,10)作y = f (x )图象的切线l ,若这样的切线有三条,求实数b 的取值范围;(2)当-1≤x ≤1时有-1≤f (x )≤1,求a ,b ,c 的所有可能的取值.苏州大学2013届高考考前指导卷(1)参考答案1.2 - i 2.2 3.64 4.- 1 5.156.2 7. 8.π2 9.(0,2π) 10.(52,5)11.a <e - 12.e 13.2 14.46415.解:(1)3(cos cos sin sin )16cos cos B C B C B C +-=,得3cos cos 3sin sin 1B C B C -=-.即3cos()1B C +=-,从而()1cos cos 3A B C =-+=.(2) 由于0πA <<,所以sin A =.又1sin 2ABC S bc A ∆==bc = 6.①由余弦定理2222cos a b c bc A =+-,得22b c +=13.② 由①②两式联立可得b = 2,c = 3或b = 3,c = 2. 16.(1)证明:∵AB = AC ,D 为BC 中点,∴AD ⊥BC .在直三棱柱ABC - A 1B 1C 1中,∵B 1B ⊥底面ABC ,AD ⊂底面ABC ,∴AD ⊥B 1B . ∵BC B 1B = B ,∴AD ⊥平面B 1BCC 1.∵B 1F ⊂平面B 1BCC 1,∴AD ⊥B 1F .在矩形B 1BCC 1中,∵C 1F = CD = a ,B 1C 1 = CF = 2a , ∴Rt △DCF ≌ Rt △FC 1B 1.∴∠CFD = ∠C 1B 1F .∴∠B 1FD = 90°.∴B 1F ⊥FD . ∵AD FD = D ,∴B 1F ⊥平面AFD . (2)∵B 1F ⊥平面AFD ,∴1113B ADF ADF V S B F -=⋅⋅△=11132AD DF B F ⨯⨯⨯⨯=(3)连EF ,EC ,设EC AF M = ,连DM ,2AE CF a == ,∴四边形AEFC 为矩形,M ∴为EC 中点.D 为BC 中点,//MD BE ∴.M D ⊂ 平面ADF ,.BE ⊄平面ADF ,//BE ∴平面ADF17.解:(1)如图,过E 作EM BC ⊥,垂足为M ,由题意得4(0tan )3MEF αα∠=≤≤, 故有60tan MF α=,60cos EF α=,8060tan AE FC α+=-, 所以60(8060tan )12cos W αα=-⨯+⨯sin 18060120cos cos ααα=-+ sin 28060cos αα-=-.(2)设sin 2()cos f ααα-=(其中00π40,tan )23ααα<=≤≤, 则22cos cos (sin )(sin 2)12sin ()cos cos f αααααααα----'==.令()0f α'=得12sin 0α-=,即1sin 2α=,得6πα=.列表所以当6α=时有max ()f α=min 80W =+答:排管的最小费用为80+6πα=.18.(1)由题意,3c a=,则a =,22222b ac c =-=, 故椭圆方程为2222132x y c c+=,即2222360x y c +-=,其中)A ,1(,0)F c -,∴直线1AF 1AF 的方程为)y x c=+,联立2222360,(),x y c y x c ⎧+-=⎪⎨=+⎪⎩得2230x cx +=,解得10x =(舍)和232x c =-,即3(,)22B c --,由对称性知3(,)2C c -. 直线BO 的方程为y x =,线段AC 的中点坐标为3()44c ,AC 的中点坐标3()44c 满足直线BO 的方程,即直线BO 平分线段AC . (2)设过P 的直线l 与椭圆交于两个不同点的坐标为1122(,),(,)M x y N x y ,点(,)Q x y ,则22211236x y c +=,22222236x y c +=.∵MP MQ PN QN=,∴设MP MQPN QN λ==,则,MP PN MQ QN λλ=-= , 求得1212,11x x x x m x λλλλ-+==-+,1212,11y y y y n y λλλλ-+==-+,∴222222121222,11x x y y mx ny λλλλ--==--, ∴2222222222221212112222223323(23)23611x x y y x y x y mx ny c λλλλλ-+-+-++===--, 由于m ,n ,C 为常数,所以点Q 恒在直线22360mx ny c +-=上.19.解 (1)令n = 1得a 2-5 = 2(a 2+5)+15,解得a 2 = 12,由已知得 (a n +1-a n )2 = 2(a n +1+a n )+15 ① (a n +2-a n +1)2 = 2(a n +2+a n +1)+15 ②将②-①得(a n +2-a n )(a n +2-2a n +1+a n ) = 2(a n +2-a n ), 由于数列{a n }单调递增,所以a n +2-a n ≠0,于是 a n +2-2a n +1+a n = 2,即(a n +2-a n +1)-(a n +1-a n ) = 2, 所以{a n +1-a n }是首项为7,公差为2的等差数列,于是 a n +1-a n = 7+2(n -1) = 2n +5,所以a n = (a n -a n -1)+(a n -1-a n -2)+…+(a 2-a 1)+a 1= (2n +3)+(2n +1)+…+7+5 = n (n +4).(2)在 S n = 2(1-b n )中令n = 1得b 1 = 2(1-b 1),解得b 1 = 23,因为S n = 2(1-b n ),S n +1 = 2(1-b n +1),相减得b n +1 = -2b n +1+2b n ,即3b n +1 = 2b n ,所以{b n }是首项和公比均为23的等比数列,所以b n = (23)n .从而a n b n = n (n +4)(23)n .设数列{a n b n }的最大项为a k b k ,则有k (k +4)(23)k ≥(k +1)(k +5)(23)k +1,且k (k +4)(23)k ≥(k -1)(k +3)(23)k -1,所以k 2≥10,且k 2-2k -9≤0,因为k 是自然数,解得k = 4.所以数列{a n b n }的最大项为a 4b 4 =51281.20.解 (1) 因为f (x )是奇函数,所以由f (-x ) = -f (x )得a = c = 0, 设切点为P (t ,4t 3+bt ),则切线l 的方程为y -(4t 3+bt ) = (12t 2+b )(x -t ),由于切线l 过点(2,10),所以10-(4t 3+bt ) = (12t 2+b )(2-t ),整理得b = 4t 3-12t 2+5, 令g (t ) = 4t 3-12t 2+5-b ,则g ′(t ) = 12t 2-24t = 12t (t -2),所以g (t )在(-∞,0)上是增函数,在(0,2)上是减函数,在(2,+∞)上是增函数,要使切线l 有三条,当且仅当g (t ) = 0有三个实数根,g (t ) = 0有三个实数根当且仅当g (0)>0,且g (2)<0,解得-11<b <5.(2)由题意,当x = ±1,±12时,均有-1≤f (x )≤1,故-1≤4+a +b +c ≤1, ① -1≤-4+a -b +c ≤1, 即-1≤4-a +b -c ≤1, ② -1≤12+a 4+b2+c ≤1, ③-1≤-12+a 4-b2+c ≤1,即-1≤12-a 4+b2-c ≤1, ④①+②得-2≤8+2b ≤2,从而b ≤-3; ③+④得-2≤1+2b ≤2,从而b ≥-3.代入①②③④得a +c = 0,a4+c = 0,从而a = c = 0.下面证明:f (x ) = 4x 3-3x 满足条件.事实上,f ′(x ) = 12x 2-3 = 3(2x +1)(2x -1),所以f (x )在(-1, -12)上单调递增,在(-12, 12)上单调递减,在(12,1)上单调递增,而f (-1) = -1,f (-12) = 1,f (12) = -1,f (1) = 1,所以当-1≤x≤1时 f (x )满足-1≤f (x )≤1.。

江苏省高考2018年高三招生考试20套模拟测试 英语试题一 含解析

江苏省高考2018年高三招生考试20套模拟测试 英语试题一 含解析

试题习题、尽在百度实战演练·高三英语20套第页(共160页)江苏省普通高等学校招生考试高三模拟测试卷(一)英语本试卷分第Ⅰ卷(选择题)和第Ⅱ卷(非选择题)两部分.满分120分,考试时间120分钟.第Ⅰ卷(选择题共80分)第一部分:听力(共两节,满分15分)第一节(共5小题;每小题1分,满分5分)听下面5段对话.每段对话后有一个小题,从题中所给的A、B、C三个选项中选出最佳选项,并标在试卷的相应位置.听完每段对话后,你都有10秒钟的时间来回答有关小题和阅读下一小题.每段对话仅读一遍.()1. Where does the conversation probably take place?A. In a cafeteria.B. In a restaurant.C. In a supermarket.()2. Why does Jack stop playing sports now?A. He is too busy.B. He has lost the interest.C. The training is too hard.()3. What does the woman mean?A. She is a visitor.B. She just moved in here.C. She knows the manager.()4. What are the speakers talking about?A. Buying DVDs.B. Borrowing DVDs.C. Sharing DVDs.()5. How does the woman find the tickets?A. They are hard to get.B. They are cheap.C. They are expensive.第二节(共10小题;每小题1分,满分10分)听下面4段对话或独白.每段对话或独白后有几个小题,从题中所给的A、B、C三个选项中选出最佳选项,并标在试卷的相应位置.听每段对话或独白前,你将有时间阅读各个小题,每小题5秒钟;听完后,各小题给出5秒钟的作答时间.每段对话或独白读两遍.听第6段材料,回答第6、7题.()6. What will the boy do after lunch?A. Have some dessert.B. Clean up his toys.C. Try a new game.()7. Who might the woman be?A. Frankie's mother.B. Frankie's babysitter.C. Frankie's sister.听第7段材料,回答第8、9题.仔细审题、认真作答.试题习题、尽在百度()8. What is Jane's problem?A. She can't have lunch with Dr. Pasteur tomorrow.B. She forgets the appointment with Dr. Pasteur.C. She can't meet Dr. Pasteur tomorrow morning at 9 a.m.()9. How long is the appointment postponed?A. Three hours and forty-five minutes.B. Four hours and fifteen minutes.C.Six hours.听第8段材料,回答第10至12题.()10. What did Mr. Tang major in the university?A. Chinese.B. Journalism.C. International operation.()11. What was Mr. Tang responsible for when he worked in a media company?A. Gathering the international news.B. Writing the current reports.C. Expanding the operation.()12. Why would Mr. Tang like to work in China?A. He can have a good chance to meet his parents.B. He can make good use of his operation ability.C. He can make good use of his Chinese and English.听第9段材料,回答第13至15题.()13. What can the iMaid do?A. Wash dishes.B. Dry the clothes.C. Clean up dirt from floors.()14. How long can the iMaid work after being charged?A. Three hours.B. Ten hours.C. Thirteen hours.()15. According to the talk, what is the best thing about the iMaid?A. The special gift worth $49.B. The price.C. The service contract.第二部分:英语基础知识运用(共两节,满分35分)第一节:单项填空(共15小题;每小题1分,满分15分)请阅读下面各题,从题中所给的A、B、C、D四个选项中,选出最佳选项.()16. —Tu Youyou and the other two scientists jointly won the 2015 Nobel Prize for medicine for their work against parasitic diseases.—They deserve it. The consequences ________ improved human health and reduced仔细审题、认真作答.试题习题、尽在百度suffering are immeasurable.A. in honor ofB. in terms ofC. in defense ofD. in hopes of()17. A teacher's job is not to tell the students what to believe or value, but to ________ them to develop a worldview for themselves.A. urgeB. rankC. persuadeD. equip()18. So why not, he reasoned, ________ the boy a few minutes to explain the whole affair?A. to spareB. sparingC. spareD. spared()19. He ________ himself to a search by the guards before entering the government building.A. objectedB. submittedC. compromisedD. identified()20. —It is reported that Papiss Cisse and Jonny Evans were charged with spitting by the Football Association.—I think spitting is one of the most disgusting things that ________ happen in the game,but yet it is not the worst.A. mustB. shallC. shouldD. can()21. Our mothers sat us down to read and paint, ________ all we really wanted to dowas to make a mess.A. sinceB. asC. unlessD. when()22. I needn't have been in such a hurry. The flight to Hong Kong ________ due to the typhoon.A. has cancelledB. was cancelledC. will be cancellingD. had cancelled()23. —A study suggests reducing energy demand in the future may ________ urban areas.—That's true. Cities need more energy than small towns or other rural areas.A. center onB. act onC. hang onD. catch on()24. Tech-free tourism refers to traveling without a mobile phone or similar devices, particularly to places ________ block or cannot access Internet and cellular signals.仔细审题、认真作答.试题习题、尽在百度A. thatB. whereC. whenD. who()25. —Have you heard of Gong Xingfang, who is experienced in taking care of mothers and newborns in Shanghai?—Yes. It is reported that she can earn 14,000 yuan ($2,252) a month now and anyone who wants to hire her has to make an ________ half a year in advance.A. assessmentB. accommodationC. appointmentD. occupation()26. My brother hopes that he ________ computer science instead of history when he graduated from the university.A. studiesB. studiedC. had studiedD. has studied()27. A Chinese student's print-like handwriting caused controversy among British Internet users,________ both praise and questions about individuality.A. drewB. drawingC. to drawD. having drawn()28. British government is planning to run a pilot scheme that will allow Chinesetourists to get a two-year tourist visa for £85—these cost £324.A. currentlyB. apparentlyC. frequentlyD. similarly()29. Some experts hold the view that fundamental construction is ________ the key tothe little island development lies.A. whichB. whatC. whereD. why()30. —His father always tells him to stop telling lies, which falls on deaf ears.—I think he will suffer the consequences. ________.A. You reap what you sowB. Justice has long armsC. Honesty is the best policyD. Lies have short legs第二节:完形填空(共20小题;每小题1分,满分20分)请认真阅读下面短文,从短文后各题所给的A、B、C、D四个选项中,选出最佳选项. The continuous presentation of frightening stories about global warming in the popular media makes us unnecessarily frightened. Even worse, it __31__ our kids.Al Gore famously __32__ how a sea-level rise of 20 feet would almost completely __33__ Florida, New York, Holland, and Shanghai, __34__ the United Nations says that such a thing willnot even happen, __35__ that sea levels will rise 20 times less than that.When __36__ with these exaggerations(夸大), some of us say that they are for a good cause,仔细审题、认真作答.试题习题、尽在百度and surely there is no __37__ done if the result is that we focus even more on dealing with climate change.Worrying of harm. exaggerations do plenty This __38__ is astonishingly wrong. Such__39__ we could do extremely about global warming means that we worry less about other things,which ) —on global warming's impact on malaria(疟疾so much more good. We focus, __40__,instead of helping the half a billion people __42__ will put more people at __41__ in 100 years—from malaria today with prevention and treatment policies that are much cheaper and dramatically more __43__ than carbon reduction would be.Exaggeration also wears out the public's __44__ to cope with global warming. If the planet iscertain to be destroyed __45__ global warming, people wonder, why should we do anything? causes it unnecessary alarm that of exaggeration, I believe, is the The __46__ costold --yearPost in The Washington mentioned nine—particularly among children. An article Alyssa, who cries about the possibility of mass animal __47__ from global warming.-year8-effective outlets for their __48__ The newspaper also reported that parents aremight be better off educating them and letting them olds' concern with dying polar bears. Theyknow that, __49__ to common belief, the global polar bear population has doubled over the past 000. __50__ the possible disappearing of summer Arctic ice, polar to about 22,century, half-bears will live on with us.D. interests C. terrifies )31. A. exhausts B. amazes (D. described C. denied B. determined ()32. A. dismissedD. expand B. flood C. reduce ()33. A. coverD. in case B. as if C. in that ()34. A. even thoughD. advocating C. estimating ()35. A. measuring B. provingD. entitled C. filled )36. A. faced B. identified (D. disadvantage C. benefit )37. A. good B. harm (D. dialogue B. argument C. story ()38. A. announcementD. whichC. where ()39. A. when B. whatD. in short C. on average )40. A. for example B. in addition (D. riskC. ease ()41. A. peace B. randomD. suffering()42. A. prohibiting B. escaping C. developing仔细审题、认真作答.试题习题、尽在百度()43. A. effective B. accurate C. complex D. temporary()44. A. ability B. sense C. willingness D. preference()45. A. due to B. except for C. regardless of D. along with()46. A. smallest B. worst C. fewest D. least()47. A. ruling out B. running out C. dropping out D. dying out()48. A. turning out B. taking over C. searching for D. pulling through()49. A. sensitive B. contrary C. related D. accustomed()50. A. Except B. Besides C. Without D. Despite第三部分:阅读理解(共15小题;每小题2分,满分30分)请认真阅读下列短文,从短文后各题所给的A、B、C、D四个选项中,选出最佳选项.ABelow are the four most famous bridges in the world.Ponte Vecchio BridgeThe Ponte Vecchio (literally “old bridge”) is a bridge built in the Middle Ages over the Arno River in Florence, Italy, the only Florentine bridge to survive World War Ⅱ. The bridge is unique for still having shops built along it, as was common in the days of the Medici. Butchers originally occupied souvenir sellers. It is said that the economic concept of bankruptcy originated here: when a merchant could not pay his debts, the table on which he sold his goods was physically broken by soldiers, and this practice was called “bancorotto (brokentable)”.Golden Gate Bridge仔细审题、认真作答.试题习题、尽在百度The Golden Gate Bridge is a suspension bridge spanning the Golden Gate, the strait between San Francisco and Marin County to the north. It is the masterwork of architect Joseph B. Strauss, whose statue graces the southern observation deck. The bridge took seven years to build, and was completed in 1937. The Golden Gate Bridge used to be the longest suspension bridge span in the world. And today it has become one of the most popular tourist attractions in San Francisco and California. Since its completion, the span length has been surpassed by eight other bridges. The famous red-orange color of the bridge was specifically chosen to make the bridge more easily visible through the thick frog that frequently covers the bridge.Millau BridgeStarted in 1998 and opened to traffic in 2005, the Millau Viaduct is a huge cable-stayedroad-bridge that spans the valley of the river Tarn near Millau in southern France. It is the tallest highway bridge in the world, with the highest pylon's summit at 343 meters—slightly taller than the Eiffel Tower. The speed limit on the bridge was reduced from 130 km/h to 110 km/h because of traffic slowing down, due to tourists taking pictures of the bridge from the vehicles. Shortly after the bridge opened to traffic, passengers were stopping to admire the landscape and the bridgeitself.Charles BridgeThe Charles Bridge is a famous stone Gothic bridge that crosses the Vltava River in Prague, Czech Republic. Its construction started in 1357 under the support of King Charles IV, and finished in the beginning of the 15th century. As the only means of crossing the river Vltava, the 仔细审题、认真作答.试题习题、尽在百度Charles Bridge was the most important connection between the Old Town and the area around Prague Castle. Connection made Prague important as a trade route between Eastern and Western Europe. Today it is one of the most visited sights in Prague with painters, owners of kiosks and other traders alongside numerous tourists crossing the bridge.()51. Of the four bridges, which one has the shortest history?A. Ponte Vecchio.B. Golden Gate Bridge.C. Millau Bridge.D. Charles Bridge.()52. Which of the following statements is TRUE about the Golden Gate Bridge?A. The span length ranks the 8th in the world.B. Its color enables travelers to see it easily on foggy days.C. It is the most popular tourist attraction in America.D. It took Joseph B. Strauss 7 years to design the bridge.()53. The Charles Bridge played an important role in Prague, Czech Republic because________.A. it attracted many famous painters thereB. it was supported by Kin Charles IVC. it was the only stone Gothic bridge crossing the Vltava RiverD. it promoted the trade between Eastern and Western EuropeBTELECOMMUTERS fall into two camps. Some sit on the sofa watching daytime soaps, pausing occasionally to check their BlackBerrys. Most, however, do real work, undistracted by meetings and talkative colleagues.In the future more people will work from home. With office space in London and New Yorkso costly, many firms save money by encouraging staff to work in their loose clothes. Instead of having to bury their noses in strangers' armpits on crowded trains, they can work via e-mail, Skype and virtual private networks.Yet, in a research published in MIT Sloan Management Review, Daniel Cable of the London Business School shows that telecommuters are less likely to be promoted. In one experiment subjects were asked to judge scenarios in which the only difference was whether the employee was at his office desk or at home. Managers rated those at the office to be more dependable and industrious, regardless of the quality of their work.仔细审题、认真作答.试题习题、尽在百度Visibility creates the illusion of value. Being the last to leave the office impresses bosses,even if you are actually larking around(胡闹) on Facebook. Oddly, this holds true at firms that explicitly encourage staff to work from home. Many Californian tech firms asked employees not to come to the office too often; yet bosses unconsciously punished those who obeyed.Remote workers understand this. Many frequently sent their bosses with progress reports to prove they are on the job. A fifth of the workers in the study admitted to leaving an e-mail or voice mail early or late in the day. Still, many are not as smart as they think. Some choose a Monday or Friday to work at home. That, says Mr. Cable, makes others think they are eager to extend the weekend.A culture of presenteeism hurts working mothers most. Many women (and some men) work from home to allow themselves the flexibility to pick up kids from school. That need not mean they produce less; only that they do it at a time and a place of their own choosing. Some firms, such as Best Buy, an electronics retailer, recognize this and try hard to evaluate staff entirely on performance. But this is not easy. Intangibles such as teamworking skills matter, too. Mr. Cable thinks homeworking will lose its stigma(污名) only when most people do it. Or perhaps when the boss is telecommuting, too.()54. What is most likely the main cause of the increasing number of telecommuters?A. Increasing location rents.B. Annoying talkative colleagues.C. High-tech mobile phones.D. Attractive daytime soaps.()55. What does the example of many California tech firms prove?A. Working at home is impractical in tech firms.B. Employees' presence at office raises their value.C. Employees should judge when to obey.D. Bosses often don't keep their promises.()56. What do wise telecommuters do to prove they are on the job?A. They give timely accounts of their work progress to their bosses.B. They check their e-mails and voice mails every day.C. They discuss the work with their bosses.D. They spend some time working on weekends.()57. What is the biggest disadvantage of working at home according to the last仔细审题、认真作答.试题习题、尽在百度paragraph?A. The traditional working culture can be hurt.B. Mothers' work may be interrupted by their kids.C. Retailers can't get enough on-site employees.D. Employees may lack chances to develop certain skills.CAlzheimer's disease has no cure. There are, however, five drugs—known and approved—thatcan slow down the development of its symptoms. The earlier such drugs are administered, the better. Unfortunately, the disease is usually first noticed when people complain to their doctors of memory problems. That is normally too late for the drugs to do much good. A simple and reliable test for Alzheimer's that can be administered to everybody over the age of about 65, before memory-loss sets in, would therefore be useful.Theo Luider, of the Erasmus University Medical Centre in Rotterdam, and his colleaguesthink they have found one—but it works only in women. They made their discovery, just reportedin the Journal of Proteome Research, by tapping into a long-term, continuing study that started in 1995 with 1,077 non-demented and otherwise healthy people aged between 60 and 90. At the beginning of the project, and subsequently during the periods 1997-99 and 2002-04, participants were brought in for a battery of neurological(神经学的) and cognitive(认知的) investigations, physical examinations, brain imaging and blood tests.During the first ten years of the study, 43 of the volunteers developed Alzheimer's diseases. When Dr. Luider compared blood samples from these people with samples from 43 of their fellow volunteers, matched for sex and age, who had remained Alzheimer's-free, he found something surprising. Levels of a substance called pregnancy zone protein had been unusually high, even before their symptoms appeared, in some of those who went on to develop Alzheimer's disease. Those “some”,it turned out, were all women. On average, levels of pregnancy zone protein in those women who went on to develop Alzheimer's were almost 60% higher than those of women who did not. In men, levels of the protein were the same for both.The reason for this curious result seems to be that the brain plaques(斑块) associated with Alzheimer's disease are themselves turning out pregnancy zone protein. Certainly, when Dr. Luider applied a chemical stain specific to that protein to the plaques of dead Alzheimer's patients 仔细审题、认真作答.试题习题、尽在百度he found the protein present in them.Confusingly, though, it was there in the plaques of both sexes. Presumably, female cells (and therefore the plaques of female brains) make more of it than male cells do. But that remains to be proved. Whatever the reason, however, this result means that women, at least, may soon be able to tell whether and when they are at risk of Alzheimer's and thus do something about it before they start losing their minds.()58. What can we learn from the first paragraph?A. No medication can slow down the development of Alzheimer's symptoms.B. To detect Alzheimer's disease before memory loss appears is vital.C. Doctors had better handle Alzheimer's disease when people are 65 years old.D. People who always complain are most likely to have Alzheimer's disease.()59. The underlined word “one”in Paragraph 2 refers to ________.A. a simple and reliable test for Alizheimer'sB. a possible cure for Alzheimer'sC. an important discovery about Alzheimer'sD. an effective and legal drug for Alzheimer's ()60. What does Dr. Luider's study tell us about the pregnancy zone protein?A. It won't go high until the symptoms of Alzheimer's appear.B. In men, levels of it remain stable for their lifetime.C. Women developing Alzheimer's usually have lower levels of it.D. The brain plaques connected with Alzheimer's produce it.()61. The passage is mainly about ________.A. patients of Alzheimer's disease and its drugsB. an introduction to the pregnancy zone proteinC. a new discovery concerning Alzheimer's diseaseD. the development stages of Alzheimer's diseaseDHe was in the first third-grade class I taught at Saint Mary's School in Morris, Minnesota.All 34 of my students were dear to me, but Mark Eklund was one in a million. Very neat in appearance, he had that happy-to-be-alive attitude that made even his occasional mischievousness delightful.Mark also talked continuously. I had to remind him again and again that talking without仔细审题、认真作答.试题习题、尽在百度permission was not acceptable. One morning my patience was growing thin when Mark talked once too often, and then I made a novice-teacher's mistake. I looked at Mark and said, “If you say one more word, I am going to tape your mouth shut!”It wasn't ten seconds later when Chuck blurted out, “Mark is talking again.”I hadn't asked any of the students to help me watch Mark, but since I had stated the punishment in front of the class, I had to act on it.I remember the scene as if it had occurred this morning. Without saying a word, I proceededto Mark's desk, tore off two pieces of tape and made a big X with them over his mouth. I then returned to the front of the room.As I glanced at Mark to see how he was doing, he winked at me. That did it! I startedlaughing. The entire class cheered as I walked back to Mark's desk, removed the tape, and shrugged my shoulders. His first words were, “Thank you for correcting me, Sister.”At the end of the year I was asked to teach junior-high math. The years flew by, and beforeI knew it Mark was in my classroom again. He was more handsome than ever and just as polite.One Friday, things just didn't feel right. We had worked hard on a new concept all week, andI sensed that the students were growing discouraged with themselves—and edgy with one another.I had to change the mood of the class before it got out of hand. So I asked them to list the namesof the other students in the room on two sheets of paper, leaving a space between each name. ThenI told them to think of the nicest thing they could say about each of their classmates and write it down. It took the remainder of the class period to finish the assignment.That Saturday, I wrote down the name of each student on a separate sheet of paper, and Ilisted what everyone else had said about that individual. On Monday I gave each student his or her list. Some of them ran two pages. Before long, the entire class was smiling. “Really?”I heard whispers. “I never knew that meant anything to anyone!”“I didn't know others liked me so much!”No one ever mentioned those papers in class again. I never knew if the students discussedthem after class or with their parents, but it didn't matter. The exercise had accomplished its purpose. The students were happy with themselves and one another again.That group of students moved on. Several years later, after I returned from a vacation, I got acall from my father. “The Eklunds called last night,”he began. “Really?”I said. “I haven't 仔细审题、认真作答.试题习题、尽在百度heard from them for several years. I wonder how Mark is.”Dad responded quietly. “Mark was killed in Vietnam,”Mark looked so handsome, somature. All I could think at that moment was, Mark, I would give all the masking tape in the worldif only you could talk to me.After the funeral, most of Mark's former classmates headed to Chuck's farmhouse for lunch.Mark's parents were there, obviously waiting for me. “Helen, we want to show you something,”his father said, taking a wallet out of his pocket. “They found this on Mark when he was killed.We thought you might recognize it.”Opening the billfold, he carefully removed two worn pieces of notebook paper that hadobviously been taped, folded and refolded many times. I knew without looking that the paperswere the ones on which I had listed all the good things each of Mark's classmates had said about him. “Thank you so much for doing that,”Mark's mother said. “As you can see, Mark treasured it.”Mark's classmates started to gather around us. Charlie smiled rather sheepishly and said, “Istill have my list. It's in the top drawer of my desk at home.”Then Vicki, another classmate, reached into her pocket-book, took out her wallet and showed her worn and ragged list to the group. “I carry this with me at all times,”Vicki said without hesitation. “I think we all saved our lists.”That's when I finally sat down and cried. I cried for Mark and for all his friends who wouldnever see him again.()62. We can conclude that when Sister Helen was a third-grade teacher, she________.A. was usually hot-tempered and impatientB. liked all the students in the class but MarkC. wasn't always sure how to discipline her studentsD. had a high expectation of the students in her class()63. The underlined word “edgy”in Paragraph 7 means “________”.A. very disappointedB. easily annoyedC. fully honestD. greatly inspired()64. Upon reading their lists for the first time, Sister Helen's students were ________.A. surprised and proudB. nervous and embarrassed仔细审题、认真作答.试题习题、尽在百度C. depressed and angryD. calm and content()65. Mark carried the notebook paper at all times because ________.A. it was a valuable gift from his dear Sister HelenB. it could ease his homesickness when in VietnamC. it was the recognition and appreciation from his classmatesD. he promised his classmates that he would treasure it第Ⅱ卷(非选择题共40分)第四部分:词汇检测(共5小题;每小题1分,满分5分)请认真阅读下列各小题,并根据上下文语境和所给首字母的提示,写出下列各句空格中的单词,注意保持语义和形式的一致.66. —Whatever b________ we are having on our shoulders, let them down for a moment,shall we?—All right. Let's enjoy the meal first.67. —I noticed the customer in red go away not altogether satisfied with Tom'sexplanations.—Definitely. She asked how the machine worked and Tom just gave a v________description about its function, which could make her even more puzzled.68. —Alice, Granny is coming. Would you give your room a t________ cleaning?—With so much homework to do, I will just mop the floor, leaving the dirty windows toJim.69. —Have you heard the news that his father's ship crashed into a rock and was broken intwo?—Yeah. Luckily, nobody was injured with the help of the soldiers s________ on the nearbyisland.70. —One more girl was bitten by a dog this morning. Worse still, nobody knows who theowner is.—It's high time to campaign for c________ registration of dogs.第五部分:同义转换(共5小题;每小题1分,满分5分)请认真阅读下列各小题的两句句子,在空格处填上一个单词,使两句句子语义保持不变.(注意:不得使用第一句中的原词)仔细审题、认真作答.试题习题、尽在百度71. —We will stick to our policy to promote relationships with the third-world countries.—It will be our ________ policy to promote relationships with the third-world countries.72. —Yan Fei, a director of Goodbye Mr. Loser thinks the success of the film lies in their devotion to telling a complete story.—Yan Fei, a director of Goodbye Mr. Loser ________ the success of the film to theirdevotion to telling a complete story.73. —Many Chinese students studying abroad have no choice but to wash dishes in the restaurants to support themselves.—In order to live on, many Chinese students studying abroad are reduced to ________ themselves out to wash dishes in the restaurants.74. —I was green with envy when I was informed that he would be promoted while Iwould not.—I was ________ when I was informed that he would be promoted while I would not.75. —Their system which relies entirely on departmental selection will surely cause lack of balance.—Their system which relies entirely on departmental selection is ________ to result in lackof balance.第六部分:任务型阅读(共10小题;每小题1分,满分10分)请认真阅读下面短文,并根据所读内容在文章后表格中的空格里填入一个最恰当的单词.注意:每个空格只填1个单词.Regret is as common an emotion as love or fear, and it can be nearly as powerful. We feel itwhen we either blame ourselves for things that turned out badly, or long to undo a choice we madein the past. The effect regret has on our lives and how we deal with regret are equally important.In some cases, regret can be disastrous. In 1995, a British man who regularly played one setof lottery numbers forgot to renew his ticket during the week that his numbers came up. He was so filled with regret and self-blame that he committed suicide. While this is an extreme consequence of regret, it can have many other lesser effects on the mind and body that can still seriously affect our lives.According to recent research, women have more regrets about romantic relationships thanmen do—not surprising, since women “value social relationships more than men”. In collectivist 仔细审题、认真作答.试题习题、尽在百度culture where many aspects of life are arranged, people feel less regret, since many choices were made for them. There was an even split between regrets about inaction (not doing something) and action (do something you wish you didn't). The research found that some regrets are more likelythan others to stay over time: people tend to hang on longer to the regret of inaction or the opportunities they have missed; meanwhile, regrets of action tend to be more recent.。

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苏州大学2018届高考考前指导卷1一、填空题:本大题共14小题,每小题5分,共计70分.不需要写出解答过程,请把答案直接填在答题卡相....应位置上..... 1.若集合{|24},{|}A x x B x x a =<=>≤,若{|34}A B x x =<<,则实数a = ▲ . 2.设复数1i 1z z +=--,其中i 为虚数单位,则||z = ▲ . 3.如图是七位评委打出的分数的茎叶统计图,去掉一个最高分和一个最低分后,所剩数据的方差为 ▲ .4.甲、乙两人下棋,已知甲获胜的概率为0.3,且两人下成和棋的概率为0.5,则乙不输的概率为 ▲ .5.根据右图所示的伪代码,当输出y 的值为 12时,则输入的x 的值 为 ▲ .6.已知双曲线C :22221(0,0x y a b a b-=>>)的离心率为2,焦点到渐近线的距离为3,则双曲线C 的焦距为 ▲ .7.设实数x ,y 满足条件01,02,21,x y y x ⎧⎪⎨⎪-⎩≤≤≤≤≥则|343|x y ++的最大值为 ▲ .8.若函数sin()(0)y x ωϕω=+>的部分图象如图所示,则ω的 值为 ▲ .9.设n S 为正项等比数列{}n a 的前n 项和,若48102a a a ⋅=,则3S 的最小值为 ▲ .10. 三棱锥BCD A -中,E 是AC 的中点,F 在AD 上,且FD AF =2,若三棱锥BEF A -的体积是2,则四棱锥ECDF B -的体积为 ▲ .11. 我国南宋时期数学家秦九韶的著作《数书九章》中记载了求三角形面积的“三斜求积”方法,相当于如下公式ABCS ∆=ABC △的周长为42,面积为84,且5cos 13B =,则边AC 的长为 ▲ . 12. 已知 O 为矩形 P 1P 2 P 3 P 4 内的一点,满足 13134,5,7OP OP PP ===,则24OP OP ⋅= ▲ .13. 已知直线22y kx k =+-与曲线232x y x -=-交于A B ,两点,平面上的动点P 满足2PA PB +≤,则||PO 的(第5题图)32最大值为 ▲ .14. 已知函数22e ()ln 0,x x a f x x x a ⎧⎪=⎨⎪<<⎩,≥,,若对任意实数k ,总存在实数0x ,使得00()f x kx =成立,则实数a 的值为▲ .二、解答题:本大题共6小题,共计90分.请在答题卡指定区域内........作答,解答时应写出必要的文字说明、证明过程或演算步骤. 15.(本小题满分14分)已知函数cos 2(sin cos )()cos sin x x x f x x x+=-.(1)求函数()f x 的定义域;(2)求函数()f x 的单调增区间.16.(本小题满分14分)如图,在四棱锥P ABCD -中,底面ABCD是矩形,BC ,,E F 分别为,BC CD 的中点, 且PF ⊥平面ABCD . 求证:(1)EF ∥平面PBD ;(2)平面PAE ⊥平面PEF .BA(第16题图)17.(本小题满分14分)某工厂两幢平行厂房间距为50m,沿前后墙边均有5m的绿化带,现在绿化带之间空地上建造一个无盖的长方体贮水池,其容积为4800m3,深度为3m,水池一组池壁与厂房平行.如果池底总造价为c元,垂直于厂房的池壁每1m2的造价为a元,平行于厂房的池壁每1m2的造价为b元,设该贮水池的底面垂直于厂房的一边的长为x(m).(1)求建造该长方体贮水池总造价y的函数关系,并写出函数的定义域;(2)试问怎样设计该贮水池能使总造价最低?并求出最低总造价.18.(本小题满分16分)如图,椭圆2222:1(0)x yE a ba b+=>>经过点(0,1)A-,右准线:2l x=,设O为坐标原点,若不与坐标轴垂直的直线与椭圆E交于不同两点,P Q(均异于点A),直线AP交l于M(点M在x轴下方).(1)求椭圆E的标准方程;(2)过右焦点F作OM的垂线与以OM为直径的圆H交于,C D两点,若CD=,求圆H的方程;(3)若直线AP与AQ的斜率之和为2,证明:直线PQ过定点,并求出该定点.(第17题图)19.(本小题满分16分)已知函数()a f x ax x =-,函数()ln g x c x =与直线2ey x =相切,其中a c ∈R ,,e 是自然对数的底数. (1)求实数c 的值;(2)设函数()()()h x f x g x =-在区间1(,e)e内有两个极值点.①求a 的取值范围;②设函数()h x 的极大值和极小值的差为M ,求实数M 的取值范围.20.(本小题满分16分)已知数列{}n a 是等差数列,数列{}n b 是等比数列,且11a =,n n a b ⎧⎫⎨⎬⎩⎭的前n 项和为n S .若1222n n n S n +=--对任意的*n ∈N 恒成立.(1)求数列{}n a ,{}n b 的通项公式;(2)若数列{}n c 满足n n nb nc a n ⎧=⎨⎩是奇数是偶数,,,.问:是否存在正整数m ,使得1187m m m c c c ++=,若存在求出m 的值,若不存在,说明理由;(3)若存在各项均为正整数、公差为d '的无穷等差数列{}n d ,满足152018d a =,且存在正整数k ,使得115,,k d d d 成等比数列,求d '的所有可能的值.苏州大学2018届高考考前指导卷(1)参考答案一、填空题1.3 2.1 3.854.0.7 56.4 7.14 8.4 9.6 10.10 11.15 12.4- 13.1 14填空题参考解答或提示 1.因为{|4}AB x a x =<<={|34}x x <<,所以a =3.2.化简得1i1iz -+=+,所以||z =1. 3.8484848687855x ++++==,218(11114)55s =++++=.4.乙不输的概率P =1-0.3=0.7 .5.由题意知20,1,0,ln ,x x y x x ⎧+=⎨>⎩≤,由12y =知,x =6.因为2,cb a=2c =,所以焦距为4. 7.画出可行域(如图),可知0,0x y >>,所以目标函数|343|343z x y x y =++=++在点1,2A ()处取得最大值14. 8.由图可知1152424ωωππ-=π,所以=4ω. 9.由48102a a a ⋅=,得22a =,设公比为0q >,则322=222226S q q q ++⋅+=≥.当且仅当=1q 取等号. 10.13A BEF B AEF AEF V V S h --∆==⋅,13B ACD ACD V S h -∆=⋅其中h 为点B 到平面AEF 的距离,而16AEF ACD S AE AF S AC AD ∆∆⋅==⋅,所以612B ACD B AEF V V --==,所以10B ECDF B ACD B AEF V V V ---=-=. 11.由5cos 13B =,得12sin 13B =,由1s i n 842ABC S ac B ∆==,得182ac =,又42a b c ++=,所以42a c b +=-,由余弦定理222222cos ()22cos (42)504b a c ac B a c ac ac B b =+-=+--=--,解得15b =. 12.连结P 2 P 4、P 1 P 3交于P 点,()()()()22222424422424444OP OP OP OP OP P P OP OP +-⋅=-=-()()()()222213311313134444OP OP P P OP OP OP OP OP OP ++-=-=-=⋅22213131313162549cos 422OP OP PP OP OP POP +-+-=⋅⋅∠===-.13. 由2(2)y k x -=-知直线过定点M 2,2(),由231=2+22x y x x -=-- 知定点M 2,2()为曲线的对称中心,即点M 为AB 的中点,所以=2|2PA PB PM +|≤,故点P 的轨迹为以M 为圆心1为半径的圆(及内部),所以|||PO OM ≤.14.设2()ln 2e x h x x =-,则1'()e x h x x =-时,'()0h x >,()h x 单调递增,当x 即2ln 2e x x ≤,所以ln 2ex x x ≤.记2el )n 0()(xx a f x g x x x x a x ⎧⎪⎪⎨⎪<<⎪==⎩,≥,,总存在实数0x ,使得0()k g x =为R ,故实数a 二、解答题15. 解(1)由题意,得cos sin x x -≠有222x k π≠π+,可知ππ4x k ≠+,所以函数()f x 的定义域为π{|π,}x x k k ≠+∈Z .(2)cos 2(sin cos )()cos sin x x x f x x x+=-=(cos sin )(sin cos )x x x x =++sin 21x =+,由ππ2π22π22k x k -++≤≤,得ππππ44k x k -++≤≤,又因为 ππ4x k ≠+, 所以函数()f x 的单增区间是ππ(π,π)44k k -++,k ∈Z . (或写成ππ[π,π)44k k -++)16. 证明:(1)因为,E F 分别为,BC CD 的中点,所以EF //BD .又EF PBD ⊄平面,BD PBD ⊂面. 所以EF ∥平面PBD .(2)不妨设AB a =,则由计算可得FE =,AE =,32FA a =, 所以222AE EF AF +=,即AE EF ⊥. 又因为PF ABCD ⊥平面,D E A ABC ⊂平面. 所以PF AE ⊥,又PFEF F =且PF EF PEF ⊂、平面.所以AE PEF ⊥平面,又因为AE PAE ⊂平面. 所以平面PAE ⊥平面PEF .17. 解(1)由题意,贮水池的底面垂直于厂房的一边长为x m ,则平行于厂房的一边长为4800m 3x,即1600m x , 所以总造价16002323y c a x b x=+⨯⨯+⨯⨯⨯, 即(]160060,40.b y c a x x x ⎛⎫=+⨯⋅+∈ ⎪⎝⎭,(2)因为0,0a b >>,所以1600b a x x ⋅+=≥ 当且仅当1600,ba x x⋅=即x =. 若b a ≤,则(0,40⎤⎦,当x =,min y c =+ 若b a >,则当(]0,40x ∈时,22216001600660b ax b y a x x ⎛⎫-⎛⎫'=⨯-=⨯< ⎪ ⎪⎝⎭⎝⎭, 所以函数y 在x ∈(0,40]上单调递减,也即当x =40时,min 240240y c a b =++. 综上可知,当b a ≤时,水池设计成垂直于厂房的一边的边长为,平行于厂房的一边的边长为,最低造价为c +b a >时,水池设计成底面边长为40m 的正方形时,最低造价为240240c a b ++元.18. 解 (1)由222212b aca b c =⎧⎪⎪=⎨⎪⎪=+⎩,解得1a b ==.所以椭圆E 的标准方程为2212x y +=.(2)设(2,)M m ,由CD OM ⊥得12CD OMk k m=-=-, 则CD 方程为2(1)y x m=--,即220x my +-=.因为圆心(1,)2m H ,则圆心H 到直线CD的距离为22|22|m d +-==圆半径为22OM r ==,且2CD =,由222()2CD d r +=,代入得2m =±. 因为点M 在x 轴下方,所以2m =-,此时圆H 方程为22(1)(1)2x y -++=. (3)设PQ 方程为:(1)y kx b b =+≠-,(0,1)A -,令1122(,),(,)P x y Q x y , 由直线AP 与AQ 的斜率之和为2得1212112y y x x +++=, 由1122,y kx b y kx b =+=+得1212(1)()22b x x k x x +++=, ①联立方程2212y kx b x y =+⎧⎪⎨+=⎪⎩,得222(12)4220k x kbx b +++-=, 所以122412kb x x k -+=+,21222212b x x k -=+代入①得,(1)(1)0b b k ++-=,由1b ≠-得10b k +-=,即1b k =-, 所以PQ 方程为1(1)1y kx k k x =+-=-+, 所以直线PQ 过定点,定点为(1,1). 19. 解(1)设直线2ey x =与函数()ln g x c x =相切与点00(,ln )P x c x , 函数()ln g x c x =在点00(,)P x y 处的切线方程为:000ln ()c y c x x x x -=-,02ec x =,把0x =,0y =代入上式得0e x =,2c =. 所以,实数c 的值为2.(2)①由(1)知()2ln ah x ax x x =--, 设函数()()()h x f x g x =-在区间1(,e)e内有两个极值点1212,()x x x x <,令22222'()0a ax x ah x a x x x -+=+-==,则220ax x a -+=,设2()2m x ax x a =-+因为121x x =,故只需0,20,(e)0,a m ∆>⎧⎪⎪>⎨⎪>⎪⎩ 所以,22e 1e 1a <<+.②因为121x x =,所以,12112212()()2ln (2ln )a aM f x f x ax x ax x x x =-=----- 11111112ln (2ln )a a ax x ax x x x =----- 2111222ln aax x x =--. 由21120ax x a -+=,得12121x a x =+,且111ex <<. 122221111112211122211122ln 4(ln )112x x x x M x x x x x x +-=--=-++.设21x t =,211e t <<,令11()4(ln )12t t t t ϕ-=-+, 222212(1)'()4()0(1)2(1)t t t t t t ϕ--=-=<++,()t ϕ在21(,1)e 上单调递减,从而21(1)()()e t ϕϕϕ<<, 所以,实数M 的取值范围是28(0,)e 1+.20. 解(1)当1n =时,1121ab =,由11a =,得12b =;由1222n n n S n +=--得222n n n S +=-①,当2n ≥时有:11122n n n S --+=- ②,由②-①得(2)2n n n a nn b =≥.分别令2,3n =可得:2212a b =,3338a b =.设{}n a 的公差为d ,{}n b 的公比为q ,则211,22123.82d q d q+⎧=⎪⎪⎨+⎪=⎪⎩ 解得1,2,d q =⎧⎨=⎩或1,32.3d q ⎧=-⎪⎪⎨⎪=⎪⎩经检验1,2,d q =⎧⎨=⎩符合条件,1,32.3d q ⎧=-⎪⎪⎨⎪=⎪⎩不合题意,舍去.故n a n =,2nn b =.(2)2n n n c n n ⎧⎪=⎨⎪⎩,是奇数,,是偶数.当m 是奇数时,由1187m m m c c c ++=,可得2(1)187mm m +=+,即18721m m m +=+, 所以186211m m =++,解得5m =, 考虑到1862,11m m ++在正整数集上分别单调递增和递减,故不存在其他解,即5m =是惟一解.当m 是偶数时,由1187m m m c c c ++=可得:118722m m m ++⋅=, 即1862m =,1862是偶数符合条件. 综上m 的值为5和1862.(3)由(1)1520182018==d a ,设{}n d 的公差为'd ,则0d '≥且'∈d Z , 当0'=d 时,显然成立;当0'>d 时,151142018,'=+=d d d所以1201814d d '=-,15(15)2018(15)k d d k d k d ''=+-=+-, 由2151=⋅k d d d ,得22018(201814)[2018(15)]''=-+-d k d ,即222201820182018(15)14201814(15)k d d k d '''=+--⨯--,所以22018(15)14201814(15)k d d k d '''-=⨯+-,因为0d '>,所以2018(15)14201814(15)k k d '-=⨯+-, 即2018201815142018141415k kd d ''-⨯=⨯+-⨯, 所以(201814)1420182018151415d k d ''-=⨯+⨯-⨯故1420182018151415201814d k d '⨯+⨯-⨯='-15(201814)1420187210091520181410097'-+⨯⨯⨯==+''--d d d , 由0d '>,得100971009d '-<,从而要使k *∈N ,只要100971,2,7,14'-=d , 又100971,144d d d *'''∈∴-==N , 综上,0144''==d d 或.。

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