复习一
人教版七年级数学上名校课堂练习章末复习(一)(含答案)
章末复习(一) 有理数基础题知识点1有理数及其分类1．四个数－3.14，0，1，2中为负数的是()A．－3.14 B．0C．1 D．22．(崇左中考)一个物体作左右方向的运动，规定向右运动4 m记作＋4 m，那么向左运动4 m 记作()A．－4 m B．4 mC．8 m D．－8 m3．下列说法正确的是()A．一个有理数不是正数就是负数B．一个有理数不是整数就是分数C．有理数是指整数、分数、正有理数、0、负有理数这五类数D．以上说法都正确知识点2数轴、相反数、绝对值、倒数4．下图中表示数轴的是()5．(深圳中考)－15的相反数是()A．15 B．－15 C．±15 D.1 156．有理数a，b，c，d在数轴上的对应点的位置如图所示，这四个数中，绝对值最大的是()A．a B．b C．c D．d 7．(咸宁中考)如图，检测4个足球，其中超过标准质量的克数记为正数，不足标准质量的克数记为负数，从轻重的角度看，最接近标准的是()8．在数轴上画出表示下列各数的点：－1.8，0，－3.5，103，612.再将这些数重新排成一行，并用“＜”把它们连接起来．9．填空：－10 －59 0.17 414 相反数 绝对值 倒数10.化简符号： (1)－[－(－212)]；(2)－[＋(－2.1)]．知识点3 有理数的运算11．若|a|＝2，|b|＝3，则|a －b|的值为( ) A ．1 B ．5 C ．1或5 D ．－112．计算： (1)(－3)＋(－8)；(2)(－7)＋(＋5)．13．计算： (1)(＋9)－9；(2)10.5－(－4.3)．14．计算： (1)(－512)×(＋2211)；(2)15×(－56)×(－214)×49；(3)－8×(12－34＋78)；(4)10×(－2.7)＋10×(－8.3)＋10.15．计算： (1)(－4)4； (2)83；(3)(25)2；(4)(－1.5)2.知识点4 有理数的应用16．某市冬季里的一天，早上6时气温是零下12 ℃，中午11时上升了5 ℃，晚上8时又上升了－8 ℃，则晚上8时的气温是________℃.17．一辆出租车在一条东西方向的大街上服务．一天上午，这辆出租车一共连续送客10次，其中4次向东行驶，每次行程为10 km ；6次向西行驶，每次行程为7 km. (1)该出租车连续10次送客后停在何处？(2)该出租车一共行驶了多少km?知识点5 科学记数法与近似数18．(长春中考)在长春市“暖房子工程”实施过程中，某工程队做了面积为632 000 m 2的外墙保暖，632 000这个数用科学记数法表示为( ) A ．63.2×104 B ．6.32×105 C ．0.632×106 D ．6.32×10619．按括号中的要求取近似值：1.504 6≈________．(结果精确到0.01) 中档题20．某大米包装袋上标注着“净含量10 kg ±150 g ”，小华从商店买了两袋大米，这两袋大米相差的克数不可能是( )A ．100 gB ．150 gC ．300 gD ．400 g 21．(毕节中考)下列说法正确的是( ) A ．一个数的绝对值一定比0大 B ．一个数的相反数一定比它本身小 C ．绝对值等于它本身的数一定是正数 D ．最小的正整数是122．对于算式2 016×(－8)＋(－2 016)×(－18)，逆用分配律写成积的形式是( ) A ．2 016×(－8－18) B ．－2 016×(－8－18) C ．2 016×(－8＋18) D ．－2 016×(－8＋18) 23．下列运算正确的是( ) A ．－57＋27＝－(57＋27)＝－1B ．－7－2×5＝－9×5＝－45C ．3÷54×45＝3÷1＝3D ．－(－3)2＝－924．(包头中考)2014年中国吸引外国投资达1 280亿美元，成为全球外国投资第一大目的地国．将1 280亿美元用科学记数法表示为( ) A ．12.8×1010美元 B ．1.28×1011美元 C ．1.28×1010美元 D ．0.128×1012美元 25．计算：1－2＋3－4＋5－6＋…＋2 015－2 016＝________． 26．若|a|＝4，|b|＝2，且ab ＜0，则a ＋b ＝________．27．如果正午12点记作0小时，午后3点钟记作＋3小时，那么上午8点钟可用负数记作________．28．我们常用的数是十进制数，计算机程序使用的是二进制数(只有数码0和1)，它们两者之间可以互相换算，如将(101)2，(1011)2换算成十进制数应为：(101)2＝1×22＋0×21＋1×20＝4＋0＋1＝5；(1011)2＝1×23＋0×22＋1×21＋1×20＝11.按此方式，将二进制(1101)2换算成十进制数的结果是________．29．将下列各数按要求分别填入相应的集合中．－9.3，6，＋314，－713，0，－100，－2.25，0.01，＋65，－27，3100，0.2·1·.正整数集合：{ …}； 负整数集合：{ …}； 正分数集合：{ …}； 负分数集合：{ …}； 整数集合：{ …}． 30．计算：(1)8＋(―12)―5―(―0.25)；(2)712×134÷(－9＋19)；(3)(－2)4÷(－4)×(12)2－12；(4)23×3－12÷(－2＋12÷3)；(5)－4×(－134)÷(－1.4)－(－32)；(6)－32－7×(27－3)＋12÷(12－13－14)．31．已知实数a ，b ，c ，d ，e ，且ab 互为倒数，c ，d 互为相反数，e 的绝对值为2，求12ab＋c ＋d 5＋e 2的值．32．若|x －2|与(y ＋7)2互为相反数，试求y x 的值．综合题33．规定△是一种新的运算符号，且a △b ＝a 2－ab ＋a －1， 例如：计算2△3＝22－2×3＋2－1＝4－6＋2－1＝－1. 请你根据上面的规定，试求4△5的值．参考答案1．A 2.A 3.B 4.B 5.A 6.A 7.C8．如图.－3.5＜－1.8＜0＜103＜612.9.10 59 －0.17 －414 10 59 0.17 414 －110 －95 10017 41710.(1)－[－(－212)]＝－212.(2)－[＋(－2.1)]＝2.1. 11.C12.(1)原式＝－(|－3|＋|－8|)＝－11. (2)原式＝－(|－7|－|＋5|)＝－2.13.(1)原式＝(＋9)＋(－9)＝0.(2)原式＝10.5＋4.3＝14.8.14.(1)原式＝－112×2411＝－12. (2)原式＝15×(－56)×(－94)×49＝[15×(－56)]×[(－94)×49]＝252×1＝252. (3)原式＝－8×12＋8×34－8×78＝－4＋6－7＝－5. (4)原式＝10×(－10)＝－100.15.(1)原式＝(－4)×(－4)×(－4)×(－4)＝256.(2)原式＝8×8×8＝512.(3)原式＝25×25＝425. (4)原式＝(－1.5)×(－1.5)＝2.25.16.－1517.(1)4×10＋6×(－7)＝40＋(－42)＝－2(km)．所以该出租车停在出发点西2 km 处．（2）|4×10|＋6×|－7|＝40＋42＝82(km)．所以该出租车共行驶82 km.18.B 19.1.50 20.D 21.D 22.C 23.D 24.B 25.－1 008 26.2或－2 27.－4小时 28.1329.6，＋65， －100， ＋314，0.01，3100，0.2·1·， －9.3，－713，－2.25，－27， 6，0，－100，＋65，30.(1)原式＝8－12－5＋14＝114. (2)原式＝152×74×110＝2116. (3)原式＝16÷(－4)×14—1＝－4×14－1＝－1－1＝－2. (4)原式＝8×3－12÷(－2＋4)＝24－12÷2＝24－6＝18.(5)原式＝－4×(－74)÷(－75)＋32＝－4×74×57＋9＝－5＋9＝4. (6)原式＝－9－2＋21＋12÷(612－412－312)＝10＋12÷(－112)＝－134. 31.因为a ，b 互为倒数，所以ab ＝1.因为c ，d 互为相反数，所以c ＋d ＝0.因为e 的绝对值为2，所以e ＝±2.所以e 2＝(±2)2＝4.所以12ab ＋c ＋d 5＋e 2＝12＋0＋4＝412. 32.由题意，得|x －2|＋(y ＋7)2＝0，因为|x －2|≥0，(y ＋7)2≥0，所以|x －2|＝(y ＋7)2＝0.解得x ＝2，y ＝－7，所以y x ＝(－7)2＝49.33.4△5＝42－4×5＋4－1＝16－20＋4－1＝－1.。
小学一年级语文下册期末分类复习一
教学目标：复习词语搭配一、填上合适的形容词（）的春天 ()的春风（）的春雨（）的小草（）的梨花（）的杏花（）的桃花（）的竹子（）的眼睛（）的睫毛（）的太阳（）的阳光（）的气球（）的小船（）的珍珠（）的世界（）的歌声（）的歌声（）的掌声（）的黎明（）的草原（）的羊群（）的公牛（）的松树（）的头发（）的头发（）的萤火虫（）的羽毛（）的羽毛（）的嘴巴（）的嘴巴（）的鼻子（）的小鸟（）的菊花（）的荷花（）的红旗（）的红领巾（）的头脑（）的双手（）的双手（）的冰花（）的眼睛（）的小河（）的天空（）的莲子（）的叶子（）的太阳（）的棉花（）的星星（）的小草（）的泥水（）的水分（）的孩子（）的东方明珠（）的云（）的小鱼（）地成长（）地观看（）地问（）地说（）地说（）地询问（）篮球（）排球（）足球二、填上合适的量词一（）春雷一（）骑手一（）松树一 () 火车一（）电脑一（）鲜花一（）眼睛一（）好字一（）比赛一（）草原一（）石碑一（）台风一（）雷雨一（）竹椅一（）桌子一（）蒲扇一（）森林一（）伞一（）小岛一（）种子一（）红旗一（）浪花一（）白云一（）冰花一 () 荷花一 () 歌曲一（）青蛙一（）松鼠一（）小鸟一（）枫叶一（）青天一（）明珠一（）珍珠一（）星星一（）巨人一（）脚印一（）草坪一（）木板一（）石头一（）小河一（）银河一（）小鱼一（）道路一（）渔船一 () 风光一（）闪电一 () 新戏一（) 军舰一（）飞船一（）牛一（）马一（）风一（）信一（）衣服一 () 明月一（）花一（）纸一（）手一（）手一（）桥一（）水一（）气一（）羊一 () 车厢一（）山一 () 饭一 () 新闻一（）油画教学目标：复习多音字读句子，用“——”划出括号中正确的读音1.小朋友随着音乐（ lâ yuâ）快乐（ lâ yuâ）地跳舞.2.一粒种（zhǒng zhîng）子睡在泥土里，他觉（juã jiào）得很暖和（huï hã）..3.满天的星星像无数（shǔ shù）颗珍珠撒在夜空，你能数（shǔ shù）的清吗？4.你趴在我的背（bâi býi）上，我背（bâi býi）着你去医院.5.我们都是少（shǎo shào）先队员.6.老师给我们教（jiüo jiào）了一首歌曲（qū qǔ）.7.帮助别人就会得（dã de）到快乐（lâ yuâ）.8.他的本子上有一行（háng xíng）大字。
高数总复习1
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《英语1》复习资料
英语1复习资料复习一1—e 2---d 3---c 4---b 5---a一.Match the phrases with Chinese translation.1. be filled with a. 和…分享2. get involved in b. 结果却…3. in terms of c. 在…方面4. only to do d. 参与某些活动5. share ... with e. 充满No final decision has been _________taken, but it seems likely that the two companies could merge in the near future.The girl was very upset because she could not get these coffee _________out of the new carpet. They said that they would innovate with persistence to________ the product in the coming year. April sunlight_________ over the water, dancing across snow-covered fields.I got a free_________ of eye shadow. Could you show me how to use itIt is generally accepted that giving advice at the right time has to________ a great deal of intelligence.Have you found the small symbols on this map which denote________places and museumsThe freshmen were recommended to read the book which was filled with _________insights.It was the old lady’s eightieth birthday, and she was sitting in a chair_________ by her children and grandchildren.三.Complete the following sentences with words or expressions from the passage.Change the form where necessary.filled with 2. were blown away 3. In terms of 4. thought to himself involved in窗体顶端Under the influence of the drug his mind _________various strange images.Some freshmen said that they_________ by that concert._________ finance, the old company has a great advantage.He_________ that he would never talk with that guy any more.If you_________ the controversy (争论), you may burn your fingers.四.Choose the right word from the brackets to fill the blanks.2. responsibly3. incredible4. diversityThere are some _________places in this area, which attract tourists every day. (historic They trusted Stephen to behave_________ while they were abroad.(responsible That’s the most _________coincidence (巧合) I’ve ever heard of! (incredible diversity definite 一1—e 2---d 3---c 4---b 5---adeliberate a. 悲惨的hollow b. 偶然碰见obstacle c. 障碍，妨碍stumble d. 中空的tragic e. 故意的二. Fill the blanks with the words given below. Change the form where necessary.1. accomplish2. Ambition3. obstacles4. dominates5. seemingly6. vision7. solutions8. releasing9. individuals10. ideal2. _________is the desire for personal achievement. It provides the motivation and determination necessary to achieve a particular end or condition.3. Women today have the chance to pursue their own careers, but still have to overcome many_________ to gain real equality.4. That school _________in baseball. This has been the third time they have won the National Youth Championship in the 21st century.5. There is_________ nothing we can do to stop the plans from going ahead. But we can at least prevent the situation from getting worse.6. _________is the desire for personal achievement. It provides the motivation and determination necessary to achieve a particular end or condition.7. Women today have the chance to pursue their own careers, but still have to overcome many_________ to gain real equality.8. That school_________ in baseball. This has been the third time they have won the National Youth Championship in the 21st century.9. There is_________ nothing we can do to stop the plans from going ahead. But we can at least prevent the situation from getting worse.10. There is_________ nothing we can do to stop the plans from going ahead. But we can at least prevent the situation from getting worse.三. Complete the following sentences with words or expressions from the passage. Change the form where necessary.三on 2. seek out out with with窗体顶端Researchers have_________ a drug that may help patients with Parkinson’s disease. This may be one of the great discoveries of the century in medicine.There are so many applicants. How can we______ a really good person for the job？Does everyone know what to do if a fire_________ This question should be asked often.4. It was my daughter’s birthday and she invited several of her good friends to the party. The air was_________the sound of children’s laughter.5. The festivities _________a huge fireworks display. Following that, there would usually be dance parties or other activities.四. Rewrite the following sentences, replacing the underlined words with their synonyms you have learned in this unit.四1. employment 2. opportunities 3. advantages 4. expenses5. accommodation(s)1. Most of this year’s graduates of our university have found jobs. ___________Your new job provides you with a lot of chances to travel around the world. ___________We should not always consider our own gains first. ___________Many people offered to pay the fees through university for the disabled young man. ___________ The International Convention Center provides top-quality hotel rooms for conference participants. ___________复习三一.Match the phrases with Chinese translation.一1—e 2---d 3---c 4---b 5---a1. apart from a. 积极投身于…2. check out b. 沉浸于3. hang out c. 闲荡；厮混4. immerse oneself in d. （在旅馆）办理退房手续，结账后离开5. throw oneself into e. 除…外二. Fill the blanks with the words given below. Change the form where necessary.二, , , , ,, , , ,1. The sort of music he listens to varies, but it __________to be popular music.2. Language is the medium of __________ , and when we learn a foreign language, we are exposed to a culture quite different from ours.3. Scientific discoveries are often __________to industrial processes.4. I hope you are not getting __________listening to me.5. Can you __________ me two good seats for the concert6. This is a __________amusing film. You'll regret if you miss it.7. He gave a __________answer to my request. I felt quite confused and disappointed.8. She was annoyed by the young man's impolite __________.9. Ever since that unhappy incident, I have tried to __________any further conflict with him.10. The driver __________the traffic light, and as a result, he ran into another car.三. Complete the following sentences with words or expressions from the passage. Change the form where necessary.三out, 2. check out, 3. giving out, 4. threw herself into, 5. immersed myself in1. They normally __________in the pub to kill time.2. I’ve been trying to __________ the restaurants in my new neighborhood to find the best one.3. Bob took a part-time job __________ handbills (传单) for a cosmetic (化妆品) company.4. Back from the holiday, she eagerly __________ the production of a new film.5. I __________ work so as to stop thinking about her.四. Complete each of the following sentences with the proper form of the word in the brackets.四 2. United 3. dramatist 4. volunteer 5. flourishing1. The American space agency has drawn up a shortlist of ten research projects that will form the basis of an __________ program to explore the planet Mars next year. (ambition)2. As the saying goes, “ __________ we stand, divided we fall.” (union)3. Eugene O'Neill wrote more than 35 plays and was the first American __________ awarded a Nobel Prize for Literature. (drama)4. I am retired and now working as a __________in an organization helping orphans. (voluntary)5. Compared to some other developing countries, the cell phone market in China is __________ . (flourish)复习参考Test one 参考一1—e 2---d 3---c 4---b 5---a二,三filled with 2. were blown away 3. In terms of 4. thought to himself involved in四 2. responsibly 3. incredible 4. diversityTest Two 参考一1—e 2---d 3---c 4---b 5---a二1. accomplish 2. Ambition 3. obstacles 4. dominates 5. seemingly6. vision7. solutions8. releasing9. individuals10. ideal三on 2. seek out out with with四 1. employment 2. opportunities 3. advantages 4. expenses 5. accommodation(s)Test Three参考一1—e 2---d 3---c 4---b 5---a二, , , , ,, , , ,三out, 2. check out, 3. giving out, 4. threw herself into, 5. immersed myself in四 2. United 3. dramatist 4. volunteer 5. flourishing。
第四章 几何图形认识初步复习(1)
• 10.如图，延长线段AB到C，使BC=3AB, 点D是线段BC的中点，如果CD=3㎝，那 么线段AC的长度是多少?
• 11.在数轴上有两个点A和B，A在原点左侧到 原点的距离为6，B在原点右侧到原点的距离为 4，M，N分别是线段AO和BO的中点，写出A 和B表示的数；求线段MN的长度。
2.线段的大小和比较
度量法
(1)线段的长短比较
叠合法 (2)线段的中点
把一条线段分成两条相等线段的点，叫做这条线段的中 点(middle point)。 例如:点B是线段AC的中点
.
A
.
B
.
C
则有:
AB=BC=
AC
AC=2AB=2BC
(3)线段的三等分点
把一条线段分成三条相等线段的两个点，叫做这条线 段的三等分点。
7部分，11部分，
把一条线段分成两条相等线段的点，叫做 这条线段的中点 如图，AB = 6厘米，点C是线段AB的中点，点D是 线段AB的中点，求线段AD的长.
. A
6厘米
？厘米
. C
.D
1 2 1 2
. B
∵ 点C是线段AB的中点， ∴ AC = BC = AB = 3厘米 ∴ CD = ∵ 点D是线段BC的中点， BC = 1.5厘米
32
11.在平面内有n个点(n≥3),其中没有 任何三个点在一条直线上,如果过任意 两点画一条直线,这n个点可以画多少 条直线? n(n-1)/2 (n2+n+2)/2
12.一条直线将平面分成两部分,两条直 线将平面分成四部分,那么三条直线将 平面最多分成几部分?四条直线将平面 最多分成几部分?n条直线呢?
（1）如果D是AC的中点，那么AD=
小学科学复习一教案
小学科学复习一教案一、教学目标1. 知识目标：通过本节课的复习，使学生能够回顾小学科学中的基本概念、实验步骤和科学常识。
2. 能力目标：培养学生的观察、思维和实验探究的能力，激发学生对科学的兴趣和好奇心。
3. 情感目标：培养学生的合作意识和团队精神，增强学生对科学实验的积极态度和热爱。
二、教学重难点1. 教学重点：回顾小学科学的基本概念、实验步骤和科学常识。
2. 教学难点：引导学生运用所学的知识，解决与现实生活相关的问题。
三、教学准备1. 教师准备：教学课件、活动实验用品、学生实验报告本。
2. 学生准备：课本、笔和纸。
四、教学过程1. 导入（15分钟）教师通过讲解一个有趣的生活现象，激发学生对科学的好奇心和兴趣。
例如，向学生展示水蒸气凝结成云朵的过程，引导学生思考并回答问题，提出相关的科学概念。
2. 复习探究（30分钟）教师通过课件展示复习内容，引导学生回顾并讨论小学科学的基本知识点、实验步骤和科学常识。
教师可采取问答、小组讨论等方式，与学生共同回顾和总结各个章节的重点内容。
（1）物质与常见现象：通过观察、实验等方式，引导学生认识物质和常见现象，如溶解、燃烧等。
（2）生物的特征与分类：通过图片、实物等展示，帮助学生认识不同生物的特征和分类方法。
（3）植物的生长与变化：通过观察植物的生长过程、实验测量等方式，引导学生了解植物的生长特点和需求。
（4）天体与日常生活：通过观察天空、了解星座等方式，让学生认识天体对日常生活的影响。
（5）健康与安全：通过讲解安全常识、小组活动等方式，培养学生的健康和安全意识。
3. 实验探究（30分钟）教师组织学生进行小组实验，让学生亲自动手进行实验探究，巩固和应用所学的科学知识。
教师提供相应的实验材料和实验指导，确保实验的安全性和有效性。
（1）实验一：水的沸点让学生利用酒精灯、温度计和水杯进行实验，观察水在何种条件下会沸腾。
引导学生用所学知识解释实验现象。
（2）实验二：植物的生长让学生以小组为单位，种植不同植物的种子，并观察其生长情况。
七年级生物上册第一单元知识点复习
生物知识点复习一1、生物具有区别于非生物的特征：(1)生物的生活需要营养 (2)生物能进行呼吸 (3)生物能排除体内产生的废物。
(4)生物能对外界刺激作出反应。
(5)生物能生长和繁殖。
(6)除病毒以外，生物都是由细胞构成的。
2、生物都生存于生物圈中。
①生物圈：包括大气圈的底部，水圈的大部和岩石圈的表面。
3、生物的生存依赖于一定的环境。
影响生物生存的因素有：生物因素(各种生物：捕食关系、竞争关系、合作关系等)和非生物因素：阳光、温度、水、空气等探究实验过程包括：提出问题，做出假设，制定计划，实施计划，得出结论，表达和交流。
生物在不断适应环境，同时也影响和改变环境。
生物的适应性是普遍存在的。
4、在一定的地域内，生物与环境构成的统一整体叫做生态系统。
生态系统由生物部分和非生物部分组成：生物部分：植物(生产者)，动物(消费者 )，细菌、真菌(分解者) 非生物部分--阳光、空气和水等5、在生态系统中，物质和能量沿着食物链和食物网流动，有毒物质能够沿着食物链积累。
食物链：在生态系统中生产者和消费者之间的关系，主要是吃与被吃的关系，这样就形成了食物链。
食物链的起始环节是生产者(如：草→兔→狐)食物网：在一个生态系统中，往往有很多条食物链，它们彼此交错连接，形成了食物网。
生态平衡：生态系统中各种生物的数量和所占的比例总是维持相对稳定的。
6、在生物圈中有着多种多样的生态系统。
生物圈是地球上最大的生态系统.其中森林生态系统有绿色水库之称，湿地生态系统具有净化水源、蓄洪抗旱的作用，农田生态系统是人工的生态系统。
▲物质和能量沿着食物链和食物网流动的。
营养级越高，生物数量越少;营养级越高，有毒物质沿食物链积累越多(富集)。
( 例如：在草原上人工种草，为了防止鸟吃草籽，用网把试验区罩上，结果发现，网罩内的草的叶子几乎被虫吃光，而未加网罩的地方，草反而生长良好。
原因是：食物链被破坏而造成生态系统平衡失调。
)1、生物学(定义)：研究生命现象和生命活动规律的科学。
第一单元复习[PPT课件]部编人教版初一七年级上册语文
![第一单元复习[PPT课件]部编人教版初一七年级上册语文](https://img.taocdn.com/s3/m/7e6510410b4e767f5acfce85.png)
菡．萏．( hàndàn ) 寒战．(zhàn ) 祷．告(dǎo ) 木雕．(diāo ) 脸颊．(jiá ) 拆．散(chāi ) 花瓣．(bàn )
攥．(zuàn ) 匿．笑( nì ) 羚．羊(línɡ ) 撒谎．(huǎnɡ ) 嫩．芽(nèn ) 分歧．( qí ) 攲．斜( qī )
单元复习一┃ 基础积累
单元复习一┃ 阅读理解
13．解释下列加点的词。
(1)太丘舍去．___离_开__。__________________________ (2)尊君在不．___通_“__否__”_。_______________________ (3)下车引．之___拉__。___________________________ (4)陈太丘与友期．行___约_定__。____________________ (5)去后乃．至____才_。___________________________ (6)元方入门不顾．__回__头__看_。_____________________
2．根据拼音写出相应的汉字。
树chà( )杈
寂mò( )
寞
憔cuì( )悴
mǒ( )眼泪 抹
荡yàng( )漾
wān( )豆 豌
水波línlín (
)粼粼
单元复习一┃ 基础积累
3．写出下列词语的同义词。
攲斜( 倾斜)
拆散(
祷告( 祈祷)
荫蔽(
霎时( 刹那)
笑柄(
) 拆开 ) 庇护
) 笑料
单元复习一┃ 基础积累
单元复习一┃ 阅读理解
┃阅读理解┃
(一)阅读下文，回答问题。 父子应是忘年交 冯骥才
①儿子考上大学时，闲话中提到费用。他忽然说：“从上初中开始，我一直 用自己的钱缴学费。”我和妻子都吃了一惊。我们活得又忙碌又糊涂，没想到 这种事。
语法复习1： 基础知识(句子成分与句子分类)
基础语法复习一（P1-10）（句子成分；简单句、并列句和复合句）一、句子成分概述（一）句子成分的定义：构成句子的各个部分叫做句子成分。
句子成分有主要成分和次要成分；主要成分有主语和谓语；次要成分有表语、宾语、定语、状语、补足语和同位语。
（二）成分导图概览：【例句】主语：Two thirds of the water is absorbed.谓语：1、简单谓语：He practices running every morning.2、复合谓语：You may keep the book for two weeks.【注】由系动词加表语也构成复合谓语。
如：We are students.表语：Our teacher of English is an American.（名词）The weather has turned cold.（形容词）The speech is exciting.（分词）Three times seven is twenty one?（数词）His job is to teach English.（不定式）His hobby（爱好）is playing football.（动名词）The machine must be out of order.（介词短语）Time is up. The class is over.（副词）The truth is that he has never been abroad.（表语从句）宾语：They went to see an exhibition（展览）yesterday.（名词）The heavy rain prevented me form coming to school on time.（代词）How many dictionaries do you have? I have five.（数词）They helped the old with their housework yesterday.（名词化形容词）He pretended not to see me.（不定式短语）I enjoy listening to popular music.（动名词短语）I think（that）he is fit for his office.（宾语从句）宾语补足语：His father named him Dongming.（名词）They painted their boat white.（形容词）Let the fresh air in.（副词）You mustn’t force him to lend his money to you.（不定式短语）We saw her entering the room.（现在分词）We found everything in the lab in good order.（介词短语）We will soon make our city what your city is now.（从句）定语：Guilin is a beautiful city.（形容词）China is a developing country; America is a developed country.（分词）There are thirty women teachers is our school.（名词）His rapid progress in English made us surprised.（代词）Our monitor is always the first to enter the classroom.（不定式短语）The teaching plan for next term has been worked out.（动名词）He is reading an article about how to learn English.（介词短语）状语：Light travels most quickly.（副词及副词性词组）He has lived in the city for ten years.（介词短语）He is proud to have passed the national college entrance examination.（不定式短语）He is in the room making a model plane.（分词短语）Wait a minute.（名词）Once you begin, you must continue.（状语从句）【巩固训练一】一、指出下列句子划线部分是什么句子成分：1. The students got on the school bus.2. He handed me the newspaper.3. I shall answer your question after class.4. What a beautiful Chinese painting!5. They went hunting together early in the morning.6. His job is to train swimmers.7. He took many photos of the palaces in Beijing.8. There is going to be an American film tonight.9. He is to leave for Shanghai tomorrow.10. His wish is to become a scientist.11. He managed to finish the work in time.12. Tom came to ask me for advice.13. He found it important to master English.14. Do you have anything else to say?15. To be honest; your pronunciation is not so good.16. Would you please tell me your address?17. He sat there, reading a newspaper.18. It is our duty to keep our classroom clean and tidy.19. He noticed a man enter the room.20. The apples tasted sweet.二、用符号划出下列短文各句中的主语（—）、谓语（＝）、宾语（～）：I hope you are very well. I'm fine, but tired. Right now it is the summer vacation and I'm helping my Dad on the farm. August is the hottest month here. It is the time of year for the rice harvest, so every day I work from dawn until dark. Sometimes we go on working after dark by the lights of our tractors. We grow rice in the south of the States, but in the north where it is colder they grow wheat. We have a lot of machines on the farm. Although the farm is large, my Dad has only two men working for him. But he employs more men for the harvest. My brother takes care of the vegetable garden. It doesn't often rain in the summer here. As a result, we have to water the vegetable garden. Every evening we pump water from a well. It then runs along channels to different parts of the garden.三、用符号划出下列短文各句中的定语（—）、状语（＝）、补语（～）：Most Saturday evenings there is a party, even at harvest time. These parties often make us very happy. We cook meat on an open fire outside. It's great! Americans eat a lot of meat — too much in my opinion. Some of my friends drink beer. I don't, because I have to drive home after the party. In your letter you asked about the time in different areas of the States. There are five different time areas in the States. In my state we are fourteen hours behind Beijing time. How many different time areas do you have in China? Well, I must stop and get some sleep. Please give my best regards to your parents.四、选择填空：1. ____ will leave for Beijing.A. Now there the manB. The man here nowC. The man who is here nowD. The man is here now2. The weather ____.A. wet and coldB. is wet and coldC. not wet and coldD. were wet and cold3. The apple tasted ____.A. sweetsB. sweetlyC. nicelyD. sweet4. He got up ____ yesterday morning.A. latelyB. lateC. latestD. latter5. The actor ______at the age of 70.A. deadB. diedC. dyedD. deaded6. ____ were all very tired, but none of ____ would stop to take a rest.A. We, usB. Us, weC. We, ourD. We, we7. He found the street much ______.A. crowdB. crowdingC. crowdedD. crowdedly8.I think _____necessary to learn English well.A. itsB. itC. thatD. that is9. The dog ____ mad.A. looksB. is lookedC. is being lookedD. was looked10.I will never forget the day ______ I joined the army.A. thatB. whenC. in whichD. where二、句子的种类（一）句子的分类导图【例句】判断下列句子所属：Be careful, boys; Don’t talk in classHow clever the boy is!He often reads English in the morning.Tom and Mike are American boys.She likes drawing and often draws pictures for the wall newspapers.You help him and he helps you.The future is bright; the road is tortuous.The foreign visitors took a lot of pictures when they were at the Great Wall.（二）简单句的五种基本句型及用法简介：英语基本句型有五个：S＋V，S＋V＋Cs，S＋V＋O，S＋V＋Oi＋Od，S＋V＋Od＋Co，其共有特征是主谓结构(S＋V)。
电路复习1
电路复习一、试求图所示电路中受控源的功率，并指出是吸收还是发出功率。
4Ω12VV二、如图所示电路为正弦稳态电路，已知电源的角频率为w ，试给出C i i i ,,21分别等于零时，电路参数之间的关系CM L L ,,,21。
三、如图所示非正弦周期电流电路中，已知,200cos 22)(,100cos 2200100)(tA t i tV t u s s =+=电路元件参数Ω=====50,125,2.0,3.0,2.021R F C H M H L H L μ，求电感L1中的电流)(1t i L 及其有效值1L I 。
四、如图所示线性电路中，已知当R5=8欧时，I5=20A ，0I =-11A,当R5=2欧时，I5=50A ，0I =-5A.试求：（1）R5为何值时消耗的功率最大，该功率是多少？（2）R5为何值时，R0消耗的功率最小，是多少？五、如图所示线性电路中，已知当R5=8欧时，I5=20 A ，0I =-11A,当R5=2欧时，I5=50A ，0I =-5A.试求：（1）R5为何值时消耗的功率最大，该功率是多少？（2）R5为何值时，R0消耗的功率最小，是多少？六、如图所示的对称三相电路中，已知V U 0380∠=∙,Ω=501j Z ,Ω=1502Z ,求电压''B A U∙,电流''A C I∙以及三角形负载的平均功率P 。
七、如图所示0100∠=∙s U ， 02∠=∙s I ，,2,901,30,45,6521=Ω=Ω=Ω=Ω=βωωLL R R 求电压源s U ∙和电流源s I ∙发出的复功率。
（15分）AB CC八、如图所示工频正选交流电路中，U=100V ,感性负载Z1的电流I1为10A ，功率因数1λ=0.5,R=20Ω。
（15分）（1） 求电源发出的有功功率，电流I 和总功率因数λ。
（2） 当电流I 限制为11A 时，应并联最小多大的电容C 。
课堂复习1需求曲线
13
价格弹性由什么决定?
为了找到需求价格弹性的决定因素，我们看下面的 这些例子。每个例子都比较了两种物品。 在每个例子中:
§ 假设两种物品的价格都上升了20% § 需求数量下降最大(百分比)的物品有最大的需求价
格弹性。它是哪种物品？为什么？
§ 这个例子告诉我们什么是决定需求价格弹性的因素。
需求价格弹性 =
需求量变动的百分比 价格变动的百分比
收益 = P x Q
§ 如果需求是缺乏弹性的，那需求价格弹性<1，需
求量变动的百分比<价格变动的百分比。
§ 需求量减少使收益减少的幅度小于价格上升使收
益增加的幅度，总收益增加。
§ 在我们下面的例子中，当你提高价格到$250时，
假定需求量只减少到10（而不是8）。
D2 D1
Q2
Q1
音乐下载的数量
4
本章我们将探索这些问题的答案：
§ 我们如何度量替代品或互补品？消费者如何对价格
做出反应？
§ 什么是弹性？ § 什么是需求价格弹性？ § 什么是供给价格弹性？ § 什么是需求收入弹性与需求的交叉价格弹性？
5
一个故事
假如由于某个突发事件——可能是中东战争，也可 能是中国经济需求旺盛，还可能是美国议会通过了 新的燃油税——导致美国汽油价格上升。 请问，消费者会对价格上升做出什么反应呢？汽油 的消费量会减少多少呢？
如果 P = $200, Q = 12 ，收益 = $2400
如果P = $250, Q=8， 收益 = $2000
价格上升所 P 增加的收益
$250
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英语期末复习专项复习 一考查常识和习语
英语期末复习专项复习一考查常识和习语一、选择题1．—Ben, you need to face fears and get over them.—That’s right. ________.A．It is easier said than done B．Better late than neverC．No pain, no gain D．Nothing is impossible to a willing heart 2．—I have tried to find the answer to the question, but failed.—Why not discuss with Tom? You see, ________.A．Great minds think alikeB．Two heads are better than oneC．A bird in the hand is worth two in the bushD．It’s better to think twice before doing something3．—Oh，dear! How can I finish so much work in 20 minutes?—Don’t worry. .We can give you a helping hand.A．Practice makes perfectB．Many hands make light workC．It never rains but it poursD．Every dog has its day4．-How do you fee1 about the new film?- I don't like the end.A．All of a sudden B．To be honestC．After all D．In this way5．—Hurry up, we must be the first to interview the pop star.—Sure.____________.A．East or west, home is the best B．The early bird catches the worm C．Many hands make light work D．Don’t put all your eggs in one basket 6．—Look at this mess! How much time do you think we need to clear it up?—It is a big job, but _________. Let’s all get started now.A．many hands make light work B．a friend in need is a friend indeedC．the early bird catches the worm D．actions speak louder than words7．My father never says he is good at cooking, but in fact he is. He always cooks delicious meals for us, that is, ________ .A．no pain, no gain B．actions speak louder than words C．practice makes perfect D．a friend in need is a friend indeed8．He is always telling his director how to run the business, that’s like “________”. A．Teaching his grandmother to suck eggs B．Keeping his ear to the groundC．A good beginning makes a bad ending D．It’s never too old to learn9．—How is everything going? --_________.A．Everything is finished B．Nothing has been doneC．Not so bad, you know D．Not doing wrong, you see10．—Good news! China’s women’s football team has entered the Tokyo 2020 Olympics after winning South Korea.— Just as the s aying goes, “________.” We can do anything if we keep working hard.A．Burn the candle at both ends B．A miss is as good as a mileC．A friend in need is a friend indeed D．Where there is a will, there is a way 11．—Steve, I hear that Peter has won another championship.—It’s not surprising. _____________. He practises hardest in the team.A．Every dog has its dayB．No pain, no gainC．Many hands make light workD．Actions speak louder than words12．In England, if you think that other people are always in a better situation than you, even when they are not, we say “________”.A．the grass is always greener on the other side B．every dog has its dayC．the early bird catches the worm D．actions speak louder than words13．________. My cousin has realized his dream after years of hard work.A．No pain, no gain B．Burn the candle at both endsC．Actions speak louder than words D．Many hands make light work14．— Dad never says that he is good at cooking, but in fact he is.— Yes. He always cooks delicious meals for us, that is ________.A．the early bird catches the worm B．many hands make light workC．burn the candle at both ends D．actions speak louder than words 15．—You know what? Susan has won a third scholarship.—That’s not surprising. ________. She devotes so much time to her study.A．The early bird catches the worm B．No pain, no gainC．Actions speak louder than words D．Practice makes perfect16．—Why can’t you trust me? Not everything you heard is true.—Maybe not. But ________.A．there is no smoke without fire B．the early bird catches the wormC．many hands make light work D．don’t put all your eggs in one basket 17．—We must work hard as a team or we will fail a second time.—Yes. Just as a saying goes, “________.”A．One finger can’t lift a small stone B．He who laughs last laughs bestC．One stone kills two birds D．One is never too old to learn18．—Mrs. Green, do you think I can get an “A” in the final exam if I start working hard now?— Of course! ________.A．Better late than never B．Many hands make light workC．You cannot burn the candle at both sides D．Action speak louder than words19．—I never thought Eddie did so good a job in the competition.—How lucky he is! Just as the saying goes “ ________”.A．Every dog has its day B．Practice makes perfectC．Actions speak louder than words D．The early bird catches the worm20．—All the people of Binhai should work together to make our hometown more beautiful.—Yes. ________.A．Many hands make light work B．Practice makes perfectC．Burn the candle at both ends D．Don’t put all your eggs in o ne basket 21．–Why can’t you trust me? Not everything you heard is true?- Maybe not. But __________________.A．out of sight, out of mind B．there is no smoke without fireC．a miss is as good as a mile D．actions speak louder than words22．You should do more and talk less. Actions speak louder than words.A．What you do isn’t important.B．What you do is as important as you say. C．What you do is more important than what you say. D．What you do is less important than you say.23．—I’ve made little progress in Engli sh this term.—Don’t worry. ________A．All roads lead to Rome B．Rome wasn’t built in a dayC．Well begun is half done D．The early bird catches the worm 24．—Dad, it’s difficult for me to clean the whole yard on my own.— Why not ask your brother for help? ________A．Use it or lose it! B．Knowledge is power!C．Practice makes perfect! D．Many hands make light work!25．Just as the saying goes, “________.” If you keep practising speaking English, you’ll be better at it.A．Practice makes perfect B．Burn the candle at both endsC．It never rains but it pours D．Many hands make light work26．Which of the following sentences is a fact?A．Beijing is the capital of China. B．The new park looks beautiful.C．Some subjects are difficult. D．I think my pet dog is very cute.27．—It's exciting that Chinese women's volleyball team won the World Cup.—Well, teamwork is important. As we know，___________.A．a good beginning is half done B．one tree can't make a forestC．actions speak louder than words D．every coin has two sides28．—Mary got the first prize in the writing competition after years of hard work.—_________.A．No pain, no gain B．A miss is as good as a mileC．Don't burn the candle at both ends D．A friend in need is a friend indeed 29．—Never give up. If you keep practicing spea king English every day. you’ll make great progress.---Thanks for encouraging me. I know .A．practice makes perfectB．it never rains but it poursC．many hands make light workD．the grass is always greener on the other side30．—Mom, I spent a whole night preparing for the exam.—My God.___don't stay up too late, or you' ll be tired out.A．You can't put your eggs in one basketB．The grass is always greener on the other sideC．You can't burn the candle at both endsD．Do as Romans do when in Rome31．—Teamwork is very important in a football match.—I think so. _______.A．The early bird catches the worm B．Every dog has its dayC．One tree can’t make a forest D．Everything comes to him who waits 32．—The year 2019 marks the 70th anniversary (周年)of the founding of the People's Republic of China.—As we know, ____. We have made great achievements in many fields.A．many hands make light work B．money isn’t everythingC．well begun is half done D．something is better than nothing33．–I have spent several nights preparing for the coming exam.-It’s bad for you to stay up too late. As the saying goes, "____________".A．You are never too old to learn. B．Actions speak louder than words.C．You can’t burn the candle at both ends.D．You can't put all your eggs in one basket. 34．—If you keep practising speaking French every day, you’ll be better at it.A．Practice makes perfect B．Many hands make light workC．Put all your eggs in one basket D．Burn the candle at both ends35．— What are people supposed to do when they meet for the first time in the US?— ________A．They’re supposed to kiss each other.B．They’re supposed to bow.C．They’re expected to shake hands.D．They’re expected to hug.36．----I promise I will work harder next term, Miss Li.---Well, just as the saying goes, “______.” I do hope that you will act at once.A．It never rains but pours B．Many hands make light workC．Actions speak louder than words D．A friend in need is a friend indeed37．—I spent the whole night preparing my report.—Don’t stay up too late, or you will b e tired out. Remember, .A．it never rains but it poursB．you can’t burn the candle at both endsC．you can’t put all your eggs in one basketD．the grass is always greener on the other side38．— Wu Dajing was the first Chinese man to win an Olympic short-track(短道) gold medal. He practiced skating as hard as he could all year round.— .A．Rome was not built in a day B．Many hands make light workC．Actions speak louder than words D．Where there is life, there is hope39．“______”means that you have to do something before others in order to be successful.A．A miss is as good as a mile B．A friend in need is a friend indeedC．The early bird catches the worm D．When in Rome, do as the Romans do 40．"___________" means "If lots of people share the work, it will make a job easier to complete."A．Burn the candle at both ends. B．Every dog has its day.C．Many hands make light work. D．A friend in need is a friend indeed.【参考答案】一、选择题1．D解析：D【详解】句意：——Ben，你需要面对恐惧，克服恐惧。
市场营销学期末复习 一至第十四章
第一章名词解释：1、市场：市场是商品经济中生产者与消费者之间实现产品（服务）价值，满足需求的交换关系、交换条件和交换过程。
2、市场营销：市场营销是个人和群体通过创造并同他人交换产品和价值以满足需求和欲望的一种社会和管理过程。
——菲利普·科特勒3、需要：指人类与生俱来的基本需要4、欲望：指得到能够满足需要的具体物品的愿望，是人受不同文化及社会环境影响而表现出来的对基本需求的特定追求。
5、需求：指人们有能力购买并愿意购买某个具体产品的欲望。
营销人员不仅要估量有多少人想要本公司的产品；更重要的是，应该了解有多少人真正愿意并且有能力购买。
第二章1、名词解释：市场营销管理：企业为实现其目标，创造、建立并保持与目标市场之间的互利交换关系而进行的分析、计划、执行与控制过程。
顾客满意：所谓顾客满意，是指顾客对一件产品满足其需要的绩效与期望进行比较所形成的感觉状态。
顾客是否满意，取决于其购买后实际感受到的绩效与期望的差异。
2、简答：市场营销观念产生的背景、实质和结果。
（市场营销观念认为，企业的一切计划与策略应以消费者为中心，正确确定目标市场的需要与欲望，比竞争者更有效地提供目标市场所需要的满足。
）背景：20世纪50到60年代，二战后，科学技术进一步发展，社会产品供应量剧增，政府推行高工资、高福利、高消费政策导致消费者购买力大幅度提高。
消费者的需求和购买欲望不断发生变化，企业间的竞争进一步加剧。
实质：市场需要什么，企业就生产和提供什么。
结果：企业的一切行为都以市场的需要作为出发点，同时又以是否满足市场的需要为归宿。
3、论述：顾客购买的总价值包括哪些内容？（顾客购买的总价值指顾客购买某一产品或服务所期望获得的一组利益。
）顾客总价值＝产品价值＋服务价值＋人员价值＋形象价值产品价值是由产品的功能、特性、品质与式样等所产生的价值。
产品价值是顾客需要的核心内容，是顾客选购产品的首要因素，是决定顾客购买总价值的关键因素。
数学六年级下册第36课时《数的认识复习 一》教案
五、全课小结：
通过这节课的复习，你们有什么收获或感受呢？关于数的认识还有很多的知识点要复习，下节课我们再来复习其它有关数的知识点。最后著名教育家乌申斯基的名言与大家分享：“装着一些片断的，没有联系的知识的头脑，就像一个乱七八糟的仓库，主人从那里是什么也找不出来的”。
请学生阅读下面的资料，并收集屏幕上的信息，在这些信息中你能找到哪些数悉的数？（整数、小数、百分数、分数、负数）
2、你知道这些数的含义吗？那这些数之间又有什么联系和区别呢？这节课我们就共同来复习小学阶段学过的与数有关的基础知识。（板书课题：数的认识）
二、梳理知识，建立网络
1、自主梳理，整理复习：
（1）请同学们用自己喜欢的方式把我们学过的数分类整理
四、巩固应用
(一)读出下面各数：
49205137580 106000000 1030500800 8000406000
(二)写出下面各数
七万五千三百六十四 四百三十万零五十六 十五亿二千零九万（三）填空、
1、地球上陆地面积大约是14802100平方千米。横线上的数读作（ ）用“四舍五入法省略亿位后面的尾数是（ Leabharlann ”个性化调整课后反思：
师：你能找到哪些数呢？它们各是什么数？对数轴你还有什么想说的？
2.生找数，重点引导说一说正、负分数和正、负小数的找法。
3.师：其实任何一个数都可以在直线上找到它对应的位置，你们能在答题卡的数轴上找到那些数的位置吗？试试看。（学生在答题卡上独立完成，投影反馈，矫正）
师：在数轴上写数完成得不错哦！敢不敢再来一题不一样的呢？
5、30÷（ ）=（ ）：30= =1.2=（ ）%
《高等数学基础》复习1：应用题(一定掌握)
注意：2010年-2021年考题中的应用题整理为例1-例7 务必掌握16分应用题！！实际问题的最大值和最小值——应用题（16分）例1 圆柱体上底中心到下底边沿的距离为l ，问当底半径与高分别为多少时，圆柱体的体积最大？ 解：设圆柱体高h 为x ，底半径r 满足222r l x =-体积为2y r h π=()()2223l x x l x x ππ=-=- ()223y l x π'=-令0y '=得3x l =（唯一驻点） 3x =-（舍掉）由实际问题知，当底半径为3l ，高3l 时，圆柱体体积最大 例2某制罐厂要生产一体积为V 的有盖圆柱形容器，问容器底半径与高各为多少时用料最省？ 解：设底半径为x ，则高为2V x π 表面积2222222V V y x x x x x ππππ=+=+224V y x x π'=- 令0y '=可得x =例3某制罐厂要生产一种体积为V 的无盖圆柱形容器，问容器底半径与高各为多少时用料最省？ （与例2区别：无盖） 解：设底半径为x ，则高为2V x π 表面积22222V V y x x x x x ππππ=+=+222V y x x π'=- 令0y '=得x =例4欲做一个底为正方形，容积为108立方米的开口容器，怎样做法用料最省？解：设底边的边长为x ，高h 2108x =用料即表面积 222210843244y x xh x xx x x =+=+=+ 24322y x x'=- 令0y '=得6x =（唯一驻点） 由实际问题知，当边长为6，高为3时用料最省例5欲做一个底为正方形，容积为62.5立方米的开口容器，怎样做法用料最省？ 解：设底边的边长为x ，高为h 262.5x =用料即表面积 222262.525044y x xh x xx x x =+=+=+ 22502y x x '=- 令0y '=解得5x =（唯一驻点） 由实际问题知，当边长为5，高为2.5时用料最省例6欲做一个底为正方形，容积为32立方米的开口容器，怎样做法用料最省？ 解：设底边的边长为x ，高为h 232x =用料即表面积 22223212844y x xh x xx x x =+=+=+ 21282y x x '=-令0y '=得4x =（唯一驻点） 由实际问题知，当边长为4，高为2时用料最省 （例4 例5 例6 只是数字变化为108 或者62.5或者32 ）例7求曲线24y x =上的点，使其到点()3,0的距离最短 解：曲线24y x =上的点(),x y 到点A ()3,0的距离公式为d === 令2229D d x x ==-+，且d 与D 在同一点上取到最小值22D x '=-令()0D x '=得1x =（唯一驻点），解出2y =±，即曲线24y x =上的点()1,2±到点A ()3,0的距离最短 练习：1. 求曲线2y x =上的点，使其到点()3,0的距离最短 解：曲线2y x =上的点(),x y 到点A （3，0）的距离公式为d ===2259D d x x ==-+，且d 与D 在同一点上取到最小值25D x '=-令()0D x '=得52x =（唯一驻点），解出2y =±，即曲线2y x =上的点5,2⎛ ⎝⎭到点A （3，0）的距离最短 2. 求曲线2y x =上的点，使其到点A ()2,0的距离最短 解： 曲线2y x =上的点到点A ()2,0的距离公式为d === 2234D d x x ==-+，且d 与2d 在同一点上取到最小值 ()23D x x '=-令()0D x '=得32x =（唯一驻点），解出y =，即曲线2y x =上的点3,22⎛± ⎝⎭到点A ()2,0的距离最短 3.求曲线22y x =上的点，使其到点A ()2,0的距离最短 解：曲线22y x =上的点到点A ()2,0的距离公式为d === 2224D d x x ==-+，且d 与2d 在同一点上取到最小值 ()22D x x '=-令()0D x '=得1x =（唯一驻点），解出y =即曲线22y x =上的点(1, A （2，0）的距离最短练习1、2、3与例7相似。
四年级下册数学 -4.4.14小数的意义和性质的整理复习(一)【教案】
4.4.14小数的意义和性质的整理复习（一）姓名徐薇刘娟王小芳李菲成绩／55.83 54.49 48.50 55.67秒50m自由泳领奖台板书设计：小数的意义和性质的整理复习(一)小数的读、写法小数的意义和性质小数的性质小数的大小比较小数的位置移动作业设计基础：1．填空题.。
（1）小数点左边第三位是（），计数单位是（）；（2）小数点右边第三位是（），计数单位是（）。
（3）0. 98是由（）个0. 1和（）个0. 01组成。
（4）0. 08里面有（）个百分之一，（）个千分之一。
（5）1.04里面有( )个0.01，有( )个0.001，（6）0. 2300的计数单位是（），化简后的计数单位是（2．在括号里填上适当的数：（1）4km80m = （）km（2）19. 08t = （）t（）kg（3）67cm = （）m（4）8. 63kg = （）g综合：3．判断：（对的打“√”、错的打“×”）（1）小数都比整数小。
（）（2）0. 1000 > 0. 0999。
（）（3）位数少的小数一定比位数多的小数小。
（）（4）0. 1写成0. 10后，小数大小没变，计数单位变了。
（）作业设计参考答案：基础：1．填空题.。
（1）百位，百（2）千分位，千分之一（3）9，8（4）8，80（5）104，1040（6）万分之一，百分之一2．在括号里填上适当的数：（1）4.08（2）19，80（3）0.67（4）8630综合：3．判断：（对的打“√”、错的打“×”）（1）（×）（2）（√）（3）（×）（4）（√）（5）（×）（6）（√）4．把每组数从大到小排列3吨100千克＞3060千克＞ 3. 05吨7. 6平方米＞7. 16平方米＞7平方米6平方分米5．0.85千克，850千克拓展：6．用3、0、5、9这几个数字和小数点写出下面各数，每个数字只能用一次。
(1)0.359（2）9.035（3）90.53。
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B C
M
N
O
D
A
若
=1﹣a，则a的取值范围是（
）
如图，正方形ABCD内接于⊙O，⊙O的直径为 2 分米， 若在这个圆面上随意抛一粒豆子，则豆子落在正方形 ABCD内的概率是
如图，某天晚8点时，一台风中心位于点O正北方向160千 米点A处，台风中心以每小时20 2 千米的速度向东南方向 移动，在距台风中心小于等于120千米的范围内将受到 台风影响，同时在点O有一辆汽车以每小时40千米的速 度向东行驶。 （1）汽车行驶了多少时间后受到台风的影响？ （2）汽车受到台风影响的时间有多少？
北 A
O
B
东
如图，已知AB为⊙O的直径，CD是弦，AB⊥CD于 E，OF⊥AC于F，BE=OF. ⑴求证：OF∥BC； ⑵求证：△AFO≌△CEB； ⑶若EB=5cm，CD= 10 3 cm，设OE=x， 求x值及阴影部分的面积.
如图，△ABC内接于⊙O，CA=CB，CD∥AB且与 OA的延长线交与点D． (1)判断CD与⊙O的位置关系并说明理由； (2)若∠ACB=120°，OA=2，求CD的长．
C
（2）某同学有如下设想：设计绿化区域为相外切 的两等圆，圆心分别为O1和O2，且O1到AB，BC， AD的距离与O2到CD，BC，AD的距离都相等，其余 为硬化地面，如图②所示，这个设想是否成立？ 若成立，求出圆的半径；若不成立，说明理由．
A O1 B 第20题图② O2 C D
如图，已知⊙O是△ABC的外接圆，AB是⊙O的直径，D 是AB延长线上的一点，AE⊥CD交DC的延长线于E， CF⊥AB于F，且CE=CF． （1）求证：DE是⊙O的切线； （2）若AB=6，BD=3，求AE和BC的长．
时间 第一个月 第二个月 清仓时
单价（元）
销量（件）
80
200
40
（2）如果批发商销售这批衬衣后获利9000元， 求第二个月的单价是多少？
将△ABC绕点B逆时针旋转到△A′BC′，使A，B， C′在同一直线上，若∠BCA=90°，∠BAC=30°， AB=4cm，则图中阴影部分面积为 cm2．
A′
E C A · F O 第23题图 B
D
如图，PA、PB与⊙O相切，切点分别为A、B，PA＝3， ∠P＝60°，若AC为⊙O的直径，则图中阴影部分的面 积为( )
A．
π 2
B．
3π 6
C．
3π 3
D．π
如图，已知直线AB与x轴、y轴分别交于A和B， OA＝4，且OA、OB长是关于x的方程x2－mx＋12＝0的两 实根，以OB为直径的⊙M与AB交于C，连结CM并延长交x 轴于N （1）求⊙M的半径。 （2）求线段AC的长。 （3）若D为OA的中点，求证：CD是⊙M的切线
30°
C
ห้องสมุดไป่ตู้C′
B
30 °
A
要对一块长60m、宽40m的矩形荒地ABCD进行绿 化和硬化． （1）设计方案如图①所示，矩形P、Q为两块绿 地，其余为硬化路面，P、Q两块绿地周围的硬化路 面宽都相等，并使两块绿地面积的和为矩形ABCD面 积的 1 ，求P、Q两块绿地周围的硬化路面的宽．
4
A P Q
D
B
第20题图①
某批发商以每件50元的价格购进800件衬衣，第一个 月以单价80 元销售，售出了200件；第二个月如果单价 不变，预计可售出200件，批发商为增加销售，决定降 价销售，根据市场调查，单价每降低1元，可多售出10 件，但最低单价应高于购进的价格；第二个月结束后， 批发商将对剩余的衬衣一次性清仓销售，清仓时单价 为40元，设第二个月单价降低x元. （1）填写下表