2017届广州市普通高中毕业班综合测试(二)(理数)

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(完整版)2017届广州市普通高中毕业班综合测试(一)(理数)试题及答案,推荐文档

(完整版)2017届广州市普通高中毕业班综合测试(一)(理数)试题及答案,推荐文档

2017届广州市普通高中毕业班综合测试(一)数学(理科)本试卷共4页,23小题, 满分150分。

考试用时120分钟。

注意事项:1. 本试卷分第I 卷(选择题)和第n 卷(非选择题)两部分.答卷前,考生务必将自 己的姓名、准考证号填写在答题卡上.2. 回答第I 卷时,选出每小题答案后,用铅笔把答题卡上对应题目的答案标号涂黑. 如 需改动,用橡皮擦干净后,再选涂其它答案标号•写在本试卷上无效.3. 回答第n 卷时,将答案写在答题卡上,写在本试卷上无效. 4•考试结束后,将本试卷和答题卡一并交回.(1)复数1的共轭复数是(B ) 13(C ) 4或 10(D ) 1 或 13、选择题:本小题共 12题,每小题 题目要求的。

在每小题给出的四个选项中,只有一项是符合(A) 1 (B) 1(C ) 1(D) 1 i(2)若集合 XX1 ,则(3) (5) 是双曲线C 的左,右焦点点P 在双曲线C 上,且PF 17,则PF ?等于(A) 1如图,网格纸上小正方形的边长为 1,粗线画出的是某几何体的正视图(等腰直角三角形)和侧视图 , 8且该几何体的体积为,则该几何体的俯视图可以是 3(7) 五个人围坐在一张圆桌旁,每个人面前放着完全相同的硬币,所有人同时翻转自己的硬币•若硬币正面朝上,则这个人站起来;若硬币正面朝下,则这个人继续坐着•那么, 没有相邻的两个人站起来的概率为,八 115115(A ) 一( B )( C )( D )2 3232 162 2X y(8) 已知F 1,F 2分别是椭圆2 1 a b 0的左,右焦点,椭圆C 上存在点Pa b使 F 1PF 2为钝角,则椭圆C 的离心率的取值范围是/A、血,1 c 迈1 (A ),1(B ) -,1(C )0,( D )0- 22 22(9)已知 p: x 0,e xax 1成立,qx:函数f Xa 1在R 上是减函数,贝U p 是q 的(A )充分不必要条件(B )必要不充分条件 (C )充要条件 (D )既不充分也不必要条件(10)《九章算术》中,将底面为长方形且有 条侧棱与底面垂直的四棱锥称之为阳马;将四个面都为直角三角形的三棱锥称之为鳖臑•若三棱锥P ABC 为鳖臑,PA 丄平面ABC ,PA AB 2, AC 4,三棱锥P ABC 的四个顶点都在球 0的球面上 则球O 的表面积为(11)若直线y 1与函数f x 2sin2x 的图象相交于点 P %,% , Q 屜,y 2,且x 1x 22,则线段PQ 与函数f x 的图象所围成的图形面积是3(A )-2-亦 (B )逅(C )43 2 (D )^3 233 3 33 3 1 2016 k (12 )已知函数f X Xx x 贝U f 的值为24 8’ k1 2017(B)(D)(6)(A) 8 (B) 12 (C ) 20(D) 24(A) 0 (B) 504 (C ) 1008 (D) 2016本卷包括必考题和选考题两部分。

2017年广州二模英语试卷

2017年广州二模英语试卷

2017年广州市普通高中毕业班综合测试(二)英语(2017.4)第二部分阅读理解(共两节,满分40分)第一节(共15小题;每小题2分,满分30分)阅读下列短文,从每题所给的四个选项中,选出最佳选项,并在答题卡上将该项涂黑。

AMany people would love to leave their jobs behind and have a life-changing adventure overseas. They imagine lying under palm trees as the sun goes down. However, life overseas is not always easy, and many are not prepared for the shock of living in an alien culture.The honeymoon periodAt first, for those who actually decide to move abroad, life is an exciting adventure. They enjoy exploring their new surroundings, and life seems like an extended holiday. They don’t mind trying the local cuisine and discovering the local culture. They can even afford to practice their foreign-language skills without fear of making mistakes.Trouble in paradiseIn many cases, when people consider moving to another country, they often fail to realize how different life will be. As time goes by, they become frustrated when language and cultural misunderstandings become a daily headache. In this stage, the visitors begin to withdraw from life in the host country and avoid spending time with local people in favor of mixing with others from their own cultural background.The road to recoveryGradually, most visitors realize they must accept the differences and not fight against them. This change encourages them to improve their language skills and slowly they manage to do the things they could easily do at home, such as opening a bank account. This new-found confidence enables them to see a side of life which very few tourists get to witness.Adjusting to life abroad can often be a real problem. The secret to overcoming it is to stop trying to change your host country: you will not succeed. If not, you risk losing your dream and having to return to the old life you wanted to leave behind.21. Why do people moving abroad feel excited at first?A. They find foreign living much easier.B. They have the necessary language skills.C. They love the adventure and exploration.D. They enjoy meeting people from different cultures.22. According to the author, what is the main problem many people moving abroad face?A. Homesickness.B. Culture shock.C. Health problems.D. Lack of employment.23. What would the author suggest people moving abroad do?A. Study the local language.B. Go on holidays frequently.C. Learn how to open a bank account.D. Seek out people from their home country.BAustralia loves interesting money. In 1988, it was the first country to replace paper money with special plastic banknotes. Now it’s introduced a new five-dollar bill so technologically advanced that many experts are calling it the money of the future!At first glance, the new note looks much like the old one. It has the same pink colour and main pictures on the front and back. But look closer, and you will notice a clear window running down the middle, surrounded by images of the yellow Prickly Moses, a type of Australian plant.Tilt(使倾斜) the note a little and you will see the Eastern Spinebill, an Australian bird, beating its wings as if trying to fly away. Turn the bill from side to side, and you will notice the picture of a small building at the bottom of the note spins, and the image of “5” changes position. While these moveable features are impressive and entertaining, that was not the reason Australian government officials spent ten years developing them. Their primary purpose was to make it impossible forcriminals to produce their own fake notes.The new five-dollar note also has something to help blind people easily identify the money. It has s raised bump alongside the top and bottom, enabling blind people to quickly determine its value.The credit for persuading the Australian government to add this all-important bump goes to 15-year-old Connor McLeod. The blind Sydney teenager came up with the idea in 2014 after being unable to tell how much money he had received for Christmas. Connor says he was so embarrassed at not being able to see the difference between notes that he only carried coins to pay for food at not being able to see the difference between notes that he only carried coins to pay for food at the school cafeteria. To convince the government officials of his idea, Connor started a website that got huge public attention.The government will add this feature to the new $10 bill which comes out in late 2017, as well as the updated $20, $50, and $100 bills that are still being designed.24. Which picture does NOT move when the banknote is tilted ?A. The bird.B. The number.C. The plants.D. The building.25. What was the main reason the Australian government created the new banknote?A. To make the note more difficult to copy.B. To show the country’s advanced technology.C. To help blind people more easily use money.D. To make the not’s appearance more attractive.26. What can we guess about Australian coins?A. They are different in size or shape.B. They are required in school cafeterias.C. They are more frequently used than notes.D. They are more convenient for young people.27. What did Connor do to persuade the government?A. He wrote a letter to the leaders.B. He organized an online meeting.C. He sought support on the Internet.D. He requested a special Christmas gift.CAt this year’s Technology Forum, speakers include world-famous people, such as Steve Wozniak, co-founder of Apple Computer, and lesser-known individuals with great ideas to change the world. One of the latter is Jonny Cohen, a high school senior, green businessman and creator of GreenShields.Since Cohen was a child, he has been innovating and inventing. When he was 12 and took science classes at Northwestern University, he saw a school bus and had an idea: what if the shape of school bus was improved to make it more fuel efficient? This would greatly reduce the amount of pollution it produced. He set about making a wind tunnel in his parents’ garage and placed small metal plates or shields on toy school buses to test them. The result: his shields redirected the airflow over and around the bus, decreased wing drag, and produced better fuel economy and less pollution.Cohen went through various experiments to improve his GreenShields invention. With the help of MIT and Cook-Illinois Bus Company, which donated a full-sized bus for Cohen’s experiments, he now has a shield model that is inexpensive and easy to attach, enabling widespread adoption.How much of an impact can these shields have on climate change? Fuel consumption for the average US school bus is seven miles per gallon. GreenShields increases fuel efficiency by 10-20%, saving about $600 per bus per year, and costs only $30 to attach. Cohen and his partners are now trying to persuade the government to put GreenShields on all school buses.With almost half-a-million school buses in America using nearly $2.5 billion of fuel per year, a consumption reduction of 10-20% would make a big difference in pollution. Not to mention the roughly $285 million in annual savings on fuel.28. What can we learn about Jonny Cohen from the text?A. He has produced GreenShields independently.B. He has been employed to improve school buses.C. He is a world-famous businessman and inventor.D. He has a talent for finding and solving problems.29.How does GreenShields make a bus more fuel efficient?A. By reducing the amount of wind drag.B. By improving the quality of fuel used.C. By providing a wind tunnel for the bus.D. By changing the shape of the bus engine.30. Where did Cohen begin testing his shields?A. At Northwestern University.B. In his parents’ garage.C. At a local bus company.D. In an MIT lab.31. What’s the intended benefit of Cohen’s invention?A. To provide school buses with cheaper fuel.B. To reduce the cost of producing school buses.C. To increase the profits of the school bus industry.D. To make school buses more environmentally-friendly.DWe all know the feeling: looking at the computer screen, pretending to be interested in our homework, even though we really feel bored. But such feelings may soon be at an end, says Dr. Harry Witchel, head of the Essex Medical School. He believes that computers of the future will notice when people feel bored and even take action to stop it.Before you get concerned, the machine won’t be reading your mind. It will be observing the many movements you make while using a computer. It’s not interested in the big movements needed to use the machine 一like moving a mouse or touching a screen — but small, barely noticeable movements like closing your eyes,moving in your seat or rubbing your face. Witchel calls these “boredom movements" and says they show how interested the person is in what they are reading or watching. The higher the interest level, the less movement!To test his theory, Witchel invited 27 people to perform various computer-based tasks. The activities ranged from playing online games (an interesting task) to reading documents like government laws that most people would find boring.A special video camera followed the participants’ movements as they completed each task. Just as the researcher expected, the “boredom movements" greatly decreased, by as much as 42%,when the subjects were very interested in what they were reading or seeing.Fortunately, Dr Witchel isn’t planning to use his results to create machines that report students who are not paying attention at school. Instead, he wants “movement sensing” technology to be built into future computers in order to improve students' computer-based learning experience.The scientist says that by measuring the students' interest level as they work, educators will be able to adjust their materials in real-time to keep students focused. Witchel also believes that the technology can provide filmmakers with honest audience opinions and in the future, help to develop more intelligent robots.32. What does the underlined word “it” in Paragraph 1 refer to?A. Homework.B. A computer.C. Boredom.D. The future.33. Why did Dr Witchel carry out his research?A. To discover how bored people move.B. To find out what makes people bored.C. To see if interested people are more active.D. To test the link between boredom and movement.34. Which movement would Witchel's technology most likely pay attention to?A. Turning off the machine.B. Typing words on a keyboard.C. Surfing quickly between webpages.D. Moving one’s head from side to side.35. How will the new technology help education, according to Witchel?A. By reducing teachers' workload.B. By maintaining students' learning interest.C. By reporting students' misbehavior in class.D. By making learning more like a computer game.第二节(共5小题,每小题2分,满分10分)根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。

广东省广州市2017届高三下学期第二次模拟考试理综试卷(含答案)

广东省广州市2017届高三下学期第二次模拟考试理综试卷(含答案)

2017年广州市普通高中毕业班综合测试(二)理科综合第I卷一、选择题:本题包括13小题,每小题6分。

在每小题给出的四个选项中,只有一项符合题目要求。

1.下列关于生物体内水和无机盐的叙述,正确的是A.在人体衰老、癌变细胞中水的含量会减少B.人体血浆渗透压的维持主要依靠Na+和K+C.种子晒干的过程中损失的主要是结合水D.缺Mg2+会影响叶肉细胞内水分解成O2和[H]2.下列关于选择透过性膜的叙述,正确的是A.细胞膜是选择透过性膜,主要由磷脂和糖类组成B.植物细胞的质壁分离现象体现了细胞壁和原生质层的选择透过性C.人工脂双层膜能让O2通过不能让Ca2+通过,属于选择透过性膜D,生物膜的选择透过性是活细胞的重要特征3.下列关于酶的实验叙述,正确的是A.利用唾液淀粉酶可以除去植物细胞壁B.用丙酮能从刀豆种子中提取到纯度较高的脲酶C.H2O2分解实验中.Fe3+、加热与过氧化氢酶降低活化能的效果依次增强D-利用pH分别为7、8、9和10的缓冲液探究pH对胃蛋白酶活性的影响4,人类免疫缺陷病毒( HIV)为逆转录病毒,由于逆转录酶缺乏校正修复功能,因而HIV的变异频率非常高。

下列叙述错误的是A.HⅣ最初侵入人体时,免疫系统能摧毁大多数病毒B.共用注射器和纹身器械是传播艾滋病的危险行为C.逆转录酶能以病毒RNA为模板合成病毒蛋白质D.同一被感染个体不同时期体内HIV的基因存在较大差异5.下列关于甲状腺激素的叙述,错误的是A.缺碘引起的甲状腺肿是反馈调节机制发挥作用的结果B.垂体产生的TSH可促进甲状腺细胞分泌甲状腺激素C.甲状腺激素分泌后经导管定向运输到相应靶细胞D.健康人体甲状腺激素分泌增多时,机体产热量增加6.下图是两种遗传病家系图,已知其中一种病为伴性遗传病,以下分析正确的是A .甲病受显性基因控制B .Ⅱ6不携带乙病致病基因C .Ⅲ8是纯合子的概率为1/2D .人群中乙病的男性患者多于女性7.化学与航空、航天密切相关,下列说法错误的是A .镁用于制造轻合金,是制造飞机、火箭的重要材料B .高纯度硅制成的光电池,可用作火星探测器的动力C .聚酯纤维属于新型无机非金属材料,可制作宇航服D .高温结构陶瓷耐高温、耐氧化,是喷气发动机的理想材料8.下列关于有机化合物的说法正确的是A .氯乙烯和溴乙烷均能发生加成反应B .花生油和玉米油都是可皂化的饱和酯类C .天然气和水煤气的主要成分都是烃类D .分子式为C10H14的单取代芳烃,其可能的结构有4种9.设NA 为阿伏加德罗常数的值。

广东省广州市2017年普通高中毕业班综合测试理科数学试卷(一)

广东省广州市2017年普通高中毕业班综合测试理科数学试卷(一)
二、填空题:本小题共4题,每小题5分.
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15.已知函数 若 ,则实数 的取值范围是__________.
16.设 为数列 的前 项和,已知 ,对任意 ,都有 ,则 ( )的最小值为__________.
A. B. C. D.
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A. B. C. D.
12.已知函数 ,则 的值为()
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第Ⅱ卷
本卷包括必考题和选考题两部分.第13~21题为必考题,每个考生都必须作答.第22~23题为选考题,考生根据要求作答.
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7.五个人围坐在一张圆桌旁,每个人面前放着完全相同的硬币,所有人同时翻转自己的硬币.若硬币正面朝上,则这个人站起来;若硬币正面朝下,则这个人继续坐着.那么,没有相邻的两个人站起来的概率为()
A. B. C. D.
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广东省广州市2017年普通高中毕业班综合测试理科数学试卷(一)
第Ⅰ卷
一、选择题:本小题共12题,每小题5分,在每小题给出的四个选项中,只有一项是符合题目要求的.
1.复数 的共轭复数是()
A. B. C. D.
2.若集合 , ,则()
A. B. C. D.
3.已知等比数列 的各项都为正数,且 , , 成等差数列,则 的值是()
三、解答题:解答应写出文字说明、证明过程或演算步骤.

2017年广州市普通高中毕业班综合测试二理科数学

2017年广州市普通高中毕业班综合测试二理科数学

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【广州】2017广州高考二模英语【无答案】

【广州】2017广州高考二模英语【无答案】

2017年广州市普通高中毕业班综合测试(二)英语2017.4第I卷第二部分阅读理解(共两节,满分40分)第一节(共15小题;每小题2分,满分30分)阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项,并在答题卡上将该项涂黑。

AMany people would love to leave their jobs behind and have a life-changing adventure overseas. They imagine lying under palm trees as the sun goes down. However, life overseas is not always easy, and many are not prepared for the shock of living in an alien culture.The honeymoon periodAt first, for those who actually decide to move abroad, life is an exciting adventure. They enjoy exploring their new surroundings, and life seems like an extended holiday. They don’t mind trying the local cuisine and discovering the local culture. They can even afford to practice their foreign-language skills without fear of making mistakes.Trouble in paradiseIn many cases, when people consider moving to another country, they often fail to realize how different life will be. As time goes by, they become frustrated when language and cultural misunderstandings become a daily headache. In this stage, the visitors begin to withdraw from life in the host country and avoid spending time with local people in favor of mixing with others from their own cultural background.The road to recoveryGradually, most visitors realize they must accept the differences and not fight against them. This change encourages them to improve their language skills and slowly they manage to do the things they could easily do at home, such as opening a bank account. This new-found confidence enables them to see a side of life which very few tourists get to witness.Adjusting to life abroad can often be a real problem. The secret to overcoming it is to stop trying to change your host country: you will not succeed. If not, you risk losing your dream and having to return to the old life youwanted to leave behind.21. Why do people moving abroad feel excited at first?A. They find foreign living much easier.B. They have the necessary language skills.C. They love the adventure and exploration.D. They enjoy meeting people from different cultures.22. According to the author, what is the main problem many people moving abroad face?A. Homesickness.B. Culture shock.C. Health problems.D. Lack of employment.23. What would the author suggest people moving abroad do?A. Study the local language.B. Go on holidays frequently.C. Learn how to open a bank account.D. Seek out people from their home country.BAustralia loves interesting money. In 1988, it was the first country to replace paper money with special plastic banknotes. Now it’s introduced a new five-dollar bill so technologically advanced that many experts are calling it the money of the future!At first glance, the new note looks much like the old one. It has the same pink color and main pictures on the front and back. But look closer, and you will notice a clear window running down the middle, surrounded by images of the yellow Prickly Moses, a type of Australian plant.Tilt (使倾斜) the note a little and you will see the Eastern Spinebill, an Australian bird, beating its wings as if trying to fly away. Turn the bill from side to side, and you will notice the picture of a small building at the bottom of the note spins, and the image of “5” changes position. While these moveable features are impressive and entertaining, that was not the reason Australian government officials spent ten years developing them. Their primary purpose was to make it impossible for criminals to produce their own fake notes.The new five-dollar note also has something to help blind people easily identify the money. It has s raised bump alongside the top and bottom, enabling blind people to quickly determine its value.The credit for persuading the Australian government to add this all-important bump goes to 15-year-oldConnor McLeod. The blind Sydney teenager came up with the idea in 2014 after being unable to tell how much money he had received for Christmas. Connor says he was so embarrassed at not being able to see the difference between notes that he only carried coins to pay for food at not being able to see the difference between notes that he only carried coins to pay for food at the school cafeteria. To convince the government officials of his idea, Connor started a website that got huge public attention.The government will add this feature to the new $10 bill which comes out in late 2017, as well as the updated $20, $50, and $100 bills that are still being designed.24. Which picture does NOT move when the banknote is tilted ?A. The bird.B. The number.C. The plants.D. The building.25. What was the main reason the Australian government created the new banknote?A. To make the note more difficult to copy.B. To show the country’s advanced technology.C. To help blind people more easily use money.D. To make the not’s appearance more attractive.26. What can we guess about Australian coins?A. They are different in size or shape.B. They are required in school cafeterias.C. They are more frequently used than notes.D. They are more convenient for young people.27. What did Connor do to persuade the government?A. He wrote a letter to the leaders.B. He organized an online meeting.C. He sought support on the Internet.D. He requested a special Christmas gift.CAt this year’s Technology Forum, speakers include world-famous people, such as Steve Wozniak, co-founder of Apple Computer, and lesser-known individuals with great ideas to change the world. One of the latter is Jonny Cohen, a high school senior, green businessman and creator of GreenShields.Since Cohen was a child, he has been innovating and inventing. When he was 12 and took science classes atNorthwestern University, he saw a school bus and had an idea: what if the shape of school bus was improved to make it more fuel efficient? This would greatly reduce the amount of pollution it produced. He set about making a wind tunnel in his parents’ garage and placed small metal plates or s hields on toy school buses to test them. The result: his shields redirected the airflow over and around the bus, decreased wing drag, and produced better fuel economy and less pollution.Cohen went through various experiments to improve his GreenShields invention. With the help of MIT and Cook-Illinois Bus Company, which donated a full-sized bus for Cohen’s experiments, he now has a shield model that is inexpensive and easy to attach, enabling widespread adoption.How much of an impact can these shields have on climate change? Fuel consumption for the average US school bus is seven miles per gallon. GreenShields increases fuel efficiency by 10-20%, saving about $600 per bus per year, and costs only $30 to attach. Cohen and his partners are now trying to persuade the government to put GreenShields on all school buses.With almost half-a-million school buses in America using nearly $2.5 billion of fuel per year, a consumption reduction of 10-20% would make a big difference in pollution. Not to mention the roughly $285 million in annual savings on fuel.28. What can we learn about Jonny Cohen from the text?A. He has produced GreenShields independently.B. He has been employed to improve school buses.C. He is a world-famous businessman and inventor.D. He has a talent for finding and solving problems.29. How does GreenShields make a bus more fuel efficient?A. By reducing the amount of wind drag.B. By improving the quality of fuel used.C. By providing a wind tunnel for the bus.D. By changing the shape of the bus engine.30. Where did Cohen begin testing his shields?A. At Northwestern University.B. In his parents’ garage.C. At a local bus company.D. In an MIT lab.31. What’s the intended benefit of Cohen’s invention?A. To provide school buses with cheaper fuel.B. To reduce the cost of producing school buses.C. To increase the profits of the school bus industry.D. To make school buses more environmentally-friendly.DWe all know the feeling: looking at the computer screen, pretending to be interested in our homework, even though we really feel bored. But such feelings may soon be at an end, says Dr. Harry Witchel, head of the Essex Medical School. He believes that computers of the future will notice when people feel bored and even take action to stop it.Before you get concerned, the machine won’t be reading your mind. It will be observing the many movements you make while using a computer. It’s not interested in the big movements needed to use the machine 一like moving a mouse or touching a screen — but small, barely noticeable movements like closing your eyes,moving in your seat or rubbing your face. Witchel calls these “boredom movements" and says they show how interested the person is in what they are reading or watching. The higher the interest level, the less movement!To test his theory, Witchel invited 27 people to perform various computer-based tasks. The activities ranged from playing online games (an interesting task) to reading documents like government laws that most people would find boring.A special video camera followed the participants’ movements as they completed each task. Just as the researcher expected, the “boredom movements" greatly decreased, by as much as 42%,when the subjects were very interested in what they were reading or seeing.Fortunately, Dr Witchel isn’t planning to use his results to create machines that report students who are not paying attention at school. Instead, he wants “movement sensing” technology to be built into future computers in order to improve students' computer-based learning experience.The scientist says that by measuring the students' interest level as they work, educators will be able to adjust their materials in real-time to keep students focused. Witchel also believes that the technology can provide filmmakers with honest audience opinions and in the future, help to develop more intelligent robots.32. What does the underlined word “it” in Paragraph 1 refer to?A. Homework.B. A computer.C. Boredom.D. The future.33. Why did Dr Witchel carry out his research?A. To discover how bored people move.B. To find out what makes people bored.C. To see if interested people are more active.D. To test the link between boredom and movement.34. Which movement would Witchel's technology most likely pay attention to?A. Turning off the machine.B. Typing words on a keyboard.C. Surfing quickly between webpages.D. Moving one’s head from side to side.35. How will the new technology help education, according to Witchel?A. By reducing teachers' workload.B. By maintaining students' learning interest.C. By reporting students' misbehavior in class.D. By making learning more like a computer game.第二节(共5小题,每小题2分,满分10分)根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。

2017届广东省广州市高三毕业班综合测试(二)理科数学试题及答案

2017届广东省广州市高三毕业班综合测试(二)理科数学试题及答案

试卷类型:A 2017年广州市普通高中毕业班综合测试(二)数学(理科)4 本试卷共4页,21小题,满分150分.考试用时120分钟注意事项:1.答卷前,考生务必用2B铅笔在“考生号”处填涂考生号.用黑色字迹的钢笔或签字笔将自己所在的市、县/区、学校以及自己的姓名和考生号、试室号、座位号填写在答题卡上.用2B铅笔将试卷类型(A)填涂在答题卡相应位置上.2.选择题每小题选出答案后,用2B铅笔把答题卡上对应题目选项的答案信息点涂黑;如需改动,用橡皮擦干净后,再选涂其他答案,答案不能答在试卷上.3.非选择题必须用黑色字迹的钢笔或签字笔作答,答案必须写在答题卡各题目指定区域内的相应位置上;如需改动,先划掉原来的答案,然后再写上新的答案;不准使用铅笔和涂改液.不按以上要求作答的答案无效.4.作答选做题时,请先用2B铅笔填涂选做题题号对应的信息点,再作答.漏涂、错涂、多涂的,答案无效.5.考生必须保持答题卡的整洁.考试结束后,将试卷和答题卡一并交回.数学(理科)试题A 第 1 页共 29 页数学(理科)试题A 第 2 页 共 29 页参考公式:球的表面积公式24S R =π,其中R 是球的半径.一、选择题:本大题共8小题,每小题5分,满分40分.在每小题给出的四个选项中,只有一项是符合题目要求的. 1.命题“若2x =,则2320x x -+=”的逆否命题是A .若2x ≠,则2320x x -+≠B .若2320x x -+=,则2x =C .若2320x x -+≠,则2x ≠D .若2x ≠,则2320x x -+=2.已知0a b >>,则下列不等关系式中正确的是A .sin sin a b> B .22log log a b< C .1122a b<D .1133ab⎛⎫⎛⎫< ⎪ ⎪⎝⎭⎝⎭3.已知函数()40,1,0,x f x x x x ⎧≥⎪=⎨⎛⎫-<⎪ ⎪⎝⎭⎩则()2f f =⎡⎤⎣⎦A .14B .12C .2D .44.函数()sin y A x ωϕ=+()0,0,0A ωϕ>><<π则此函数的解析式为A .3sin y x ππ⎛⎫=+ ⎪44⎝⎭B .y =C .3sin y x ππ⎛⎫=+ ⎪24⎝⎭D .3sin y x π3π⎛⎫=+ ⎪24⎝⎭图1数学(理科)试题A 第 3 页 共 29 页5.已知函数()223f x x x =-++,若在区间[]4,4-上任取一个实数0x ,则使()00f x ≥成立的概率为A .425 B .12C .23D .16.如图2,圆锥的底面直径2AB =,母线长3VA =,点C在母线VB 上,且1VC =,有一只蚂蚁沿圆锥的侧面从点A 到达点C ,则这只蚂蚁爬行的最短距离是A C .3D .27.已知两定点()1,0A -,()1,0B ,若直线l 上存在点M ,使得3MA MB +=,则称直线l 为“M 型直线”.给出下列直线:①2x =;②3y x =+;③21y x =--;④1y =;⑤23y x =+.其中是“M型直线”的条数为A .1B .2C .3D .48.设(),P x y 是函数()y f x =的图象上一点,向量()()51,2x =-a ,()1,2y x =-b ,且//a b .数列{}n a是公差不为0的等差数列,且()()()12936f a f a f a ++⋅⋅⋅+=,则129a a a ++⋅⋅⋅+=A.0B.9C.18D.36AV CB图2数学(理科)试题A 第 4 页 共 29 页二、填空题:本大题共7小题,考生作答6小题,每小题5分,满分30分.(一)必做题(9~13题)9.已知i 为虚数单位,复数1i 1iz -=+,则z = .10.执行如图3所示的程序框图,则输出的z 的值是 .11.已知()sin 6f x x π⎛⎫=+ ⎪⎝⎭,若3cos 5α=02απ⎛⎫<< ⎪⎝⎭,则12f απ⎛⎫+= ⎪⎝⎭. 12.5名志愿者中安排4人在周六、周日两天参加社区公益活动.若每天安排2人,则不同的安排方案共有_________种(用数字作答).13.在边长为1的正方形ABCD 中,以A 为起点,其余顶点为终点的向量分别为1a ,2a ,3a ;以C 为起点,其余顶点为终点的向量分别为1c ,2c ,3c .若m 为()()i j s t +∙+a a c c 的最小值,其中{}{},1,2,3i j ⊆,{}{},1,2,3s t ⊆,则m = .(二)选做题(14~15题,考生只能从中选做一题) 14.(几何证明选讲选做题)B ACDEFG 图4数学(理科)试题A 第 5 页 共 29 页如图4,在平行四边形ABCD 中,4AB =,点E 为边DC 的中点,AE 与BC 的延长线交于点F,且AE 平分BAD ∠,作DG AE ⊥,垂足为G ,若1DG =,则AF 的长为 . 15.(坐标系与参数方程选做题)在平面直角坐标系中,已知曲线1C 和2C 的方程分别为32,12x t y t=-⎧⎨=-⎩(t 为参数)和24,2x t y t=⎧⎨=⎩(t 为参数),则曲线1C 和2C 的交点有 个. 三、解答题:本大题共6小题,满分80分.解答须写出文字说明、证明过程和演算步骤. 16.(本小题满分12分)已知△ABC 的三边a ,b ,c 所对的角分别为A ,B ,C ,且::7:5:3a b c =. (1)求cos A 的值; (2)若△ABC的面积为,求△ABC 外接圆半径的大小.17.(本小题满分12分)某市为了宣传环保知识,举办了一次“环保知识知多少”的问卷调份,统计结果如下面的图表所示.数学(理科)试题A 第 6 页 共 29 页(1)分别求出a ,b ,c ,n 的值;(2)从第3,4组答对全卷的人中用分层抽样的方法抽取6人,在所抽取的6人中随机抽取2人授予“环保之星”,记X 为第3组被授予“环保之星”的人数,求X 的分布列与数学期望.18.(本小题满分14分)如图5,已知六棱柱111111ABCDEF A BC D E F -的侧棱垂直于底面,侧棱长与底面边长都为3,M ,N 分别是棱AB ,1AA 上的点,且1AM AN ==.(1)证明:M ,N ,1E ,D 四点共面;(2)求直线BC 与平面1MNE D 所成角的正弦值.19.(本小题满分14分)已知点(),n n n P a b ()n ∈*N 在直线l :31y x =+上,1P 是直线l 与y 轴的交点,数列{}n a 是公差为1的等差数列. (1)求数列{}n a ,{}n b 的通项公式; (2)求证:22212131111116n PP PP PP ++++<.C 1ABA 1B 1 D 1CDMNEFE 1F 1图5数学(理科)试题A 第 7 页 共 29 页20.(本小题满分14分)已知圆心在x 轴上的圆C 过点()0,0和()1,1-,圆D的方程为()2244x y -+=.(1)求圆C 的方程;(2)由圆D 上的动点P 向圆C 作两条切线分别交y 轴于A ,B 两点,求AB的取值范围.21.(本小题满分14分)已知函数()ln f x a x =-11x x -+,()e x g x =(其中e 为自然对数的底数). (1)若函数()f x 在区间()0,1内是增函数,求实数a 的取值范围; (2)当0b >时,函数()g x 的图象C 上有两点(),e b P b ,(),e b Q b --,过点P ,Q 作图象C 的切线分别记为1l ,2l ,设1l 与2l 的交点为()00,M x y ,证明00x >.2017年广州市普通高中毕业班综合测试(二)数学(理科)试题参考答案及评分标准说明:1.参考答案与评分标准给出了一种或几种解法供参考,如果考生的解法与参考答案不同,可根据试题主要考查的知识点和能力比照评分标准给以相应的分数.2.对解答题中的计算题,当考生的解答在某一步出现错误时,如果后继部分的解答未改变该题的内容和难度,可视影响的程度决定后继部分的得分,但所给分数不得超过该部分正确解答应得分数的一半;如果后继部分的解答有较严重的错误,就不再给分.3.解答右端所注分数,表示考生正确做到这一步应得的累加分数.4.只给整数分数,选择题和填空题不给中间分.一、选择题:本大题考查基本知识和基本运算.共8小题,每小题,满分40分.二、填空题:本大题考查基本知识和基本运算,体现选择性.共7小题,每小题,满分30分.其中14~15题是选做题,考生只能选做一题.数学(理科)试题A 第 8 页共 29 页数学(理科)试题A 第 9 页 共 29 页16.(本小题满分12分) 解:(1)因为::7:5:3a b c =,所以可设7a k=,5b k=,3c k =()0k >, (2)分由余弦定理得,222cos 2b c a A bc +-=()()()222537253k k k k k+-=⨯⨯…………………………………………………………3分12=-.………………………………………………………………………………………………4分 (2)由(1)知,1cos 2A =-,因为A 是△ABC 的内角, 所以sin A 2=………………6分数学(理科)试题A 第 10 页 共 29 页由(1)知5b k =,3c k =, 因为△ABC的面积为,所以1sin 2bc A =8分即1532k k ⨯⨯= 解得k =……………………10分 由正弦定理2sin aR A=,即72sin k R A ==,…………………………………………………11分解得14R =. 所以△ABC外接圆半径的大小为14. (12)分17.(本小题满分12分)解:(1)根据频率直方分布图,得()0.0100.0250.035101c +++⨯=,解得0.03c =.……………………………………………………………………………………………1分第3组人数为105.05=÷,所以1001.010=÷=n . (2)分数学(理科)试题A 第 11 页 共 29 页第1组人数为1000.3535⨯=,所以28350.8b =÷=. (3)分 第4组人数为2525.0100=⨯,所以250.410a =⨯=. (4)分(2)因为第3,4组答对全卷的人的比为5:101:2=,所以第3,4组应依次抽取2人,4人.…………………………………………………………………5分依题意X的取值为0,1,2.……………………………………………………………………………6分()022426C C 20C 5P X ===,…………………………………………………………………………………7分()112426C C 81C 15P X ===,………………………………………………………………………………8分()202426C C 12C 15P X ===,………………………………………………………………………………9分所以X 的分布列为:………………………………………10分数学(理科)试题A 第 12 页所以2812012515153EX =⨯+⨯+⨯=. ………………………………………………………………12分 18.(本小题满分14分)第(1)问用几何法,第(2)问用向量法: (1)证明:连接1A B ,11B D ,BD ,11A E , 在四边形1111A B D E 中,1111A E B D 且1111=A E B D , 在四边形11BB D D 中,11BD B D 且11=BD B D , 所以11A E BD 且11=A E BD ,所以四边形11A BDE 是平行四边形.所以11A B E D .………………………………2分 在△1ABA 中,1AM AN ==,13AB AA ==, 所以1AMANABAA =,所以1MN BA .…………………………………………………………………………………………4分 所以1MN DE . 所以M,N,1E ,D四点共分C 1A BA 1B 1D 1CDMNEF E 1F 1数学(理科)试题A 第 13 页 共 29 页(2)解:以点E 为坐标原点,EA ,ED ,1EE 所在的直线分别为x 轴,y 轴,z 轴,建立如图的空间直角坐标系,则()B,9,02C ⎫⎪⎪⎝⎭,()0,3,0D , ()10,0,3E,()M ,…………………………8分则3,02BC ⎛⎫= ⎪ ⎪⎝⎭,()10,3,3DE =- ,()2,0DM =-.……………………………………………………………………………………10分设(),,x y z =n 是平面1MNE D 的法向量,则10,0.DE DM ⎧=⎪⎨=⎪⎩ n n即330,20.y z y -+=⎧⎪⎨-=⎪⎩取y =2x =,z = 所以(=n 是平面1MNE D的一个法向量.………………………………………………12分 设直线BC 与平面1MNE D 所成的角为θ,则sin BCBCθ=n n116==.故直线BC与平面1MNE D所成角的正弦值为数学(理科)试题A 第 14 页 共 29 页116.………………………………………………14分 第(1)(2)问均用向量法:(1)证明:以点E 为坐标原点,EA ,ED ,1EE 所在的直线分别为x 轴,y 轴,z则()B ,9,02C ⎫⎪⎪⎝⎭,()0,3,0D , ()10,0,3E ,()M ,()N 所以()10,3,3DE =- ,()0,1,1MN =-. 因为13DE MN =,且MN 与1DE 不重合,所以1DE MN .…………………………………………5分 所以M,N,1E ,D四点共面.………………………………………………………………………6分(2)解:由(1)知3,022BC ⎛⎫=- ⎪ ⎪⎝⎭,()10,3,3DE =-,()2,0DM =-.………………10分(特别说明:由于给分板(1)6分(2)8分,相当于把(1)中建系与写点坐标只给2分在此加2分)设(),,x y z =n 是平面1MNE D 的法向量,则10,0.DE DM ⎧=⎪⎨=⎪⎩ n n 即330,20.y z y -+=⎧⎪⎨-=⎪⎩数学(理科)试题A 第 15 页 共 29 页取y =2x =,z = 所以(=n 是平面1MNE D的一个法向量.………………………………………………12分 设直线1BC 与平面1MNE D 所成的角为θ,则sin BCBCθ=n n==.故直线BC与平面1MNE D所成角的正弦值为.………………………………………………14分 第(1)(2)问均用几何法:(1)证明:连接1A B ,11B D ,BD ,11A E , 在四边形1111A B D E 中,1111A E B D 且1111=A E B D , 在四边形11BB D D 中,11BD B D 且11=BD B D , 所以11A E BD 且11=A E BD ,所以四边形11A BDE 是平行四边形.所以11A B E D .………………………………2分 在△1ABA 中,1AM AN ==,13AB AA ==, 所以1AMANABAA =,所以C 1A BA 1B 1 D 1CDMNEFE 1F 1数学(理科)试题A 第 16 页 共 29 页1MN BA .…………………………………………………………………………………………4分 所以1MN DE . 所以M,N,1E ,D四点共面.………………………………………………………………………6分(2)连接AD ,因为BC AD ,所以直线AD 与平面1MNE D 所成的角即为直线BC 与平面1MNE D 所成的角.…………………7分连接DN ,设点A 到平面DMN 的距离为h ,直线AD 与平面1MNE D 所成的角为θ,则sin hADθ=.……………………………………………………………………………………………8分因为A DMN D AMNV V --=,即1133DMN AMN S h S DB ∆∆⨯⨯=⨯⨯.…………………………………………9分 在边长为3的正六边形ABCDEF中,DB =6DA =, 在△ADM 中,6DA =,1AM =,60DAM ∠= ,由余弦定理可得,DM =在Rt △DAN 中,6DA =,1AN =,所以DN = 在Rt △AMN 中,1AM =,1AN =,所以MN在△DMN中,DM =DN =MN =数学(理科)试题A 第 17 页 共 29 页由余弦定理可得,cos DMN ∠=,所以sin DMN ∠=所以1sin 22DMN S MN DM DMN ∆=⨯⨯⨯∠=.…………………………………………………11分又12AMN S ∆=,……………………………………………………………………………………………12分所以AMN DMN S DB h S ∆∆⨯==………………13分所以sin 116h AD θ==故直线BC与平面1MNE D所成角的正弦值为116.………………………………………………14分19.(本小题满分14分)(1)解:因为()111,P a b 是直线l :31y x =+与y 轴的交点()0,1, 所以10a =,11b =.……………………………………………………………………………………2分数学(理科)试题A 第 18 页 共 29 页因为数列{}n a 是公差为1的等差数列, 所以1n a n =-.……………………………………………………………………………………………4分因为点(),n n n P a b 在直线l :31y x =+上, 所以31n n b a =+32n =-.所以数列{}n a ,{}n b 的通项公式分别为1n a n =-,32n b n =-()*n ∈N .………………………6分(2)证明:因为()10,1P ,()1,32n P n n --,所以()1,31n P n n ++. 所以()222211310n PP n n n +=+=.………………………………………………………………………7分 所以222121311111n PP PP PP ++++22211111012n ⎛⎫=+++ ⎪⎝⎭.……………………………………8分 因为()()222114411241212121214n n n n n n n ⎛⎫<===- ⎪--+-+⎝⎭-,……………………………10分所以,当2n ≥时,222121311111n PP PP PP ++++数学(理科)试题A 第 19 页 共 29 页111111210352121n n ⎡⎤⎛⎫<+-++- ⎪⎢⎥-+⎝⎭⎣⎦ ……………………………………………………………11分15110321n ⎛⎫=- ⎪+⎝⎭………………………………………………………………………………………12分16<.又当1n =时,212111106PP =<.………………………………………………………………………13分所以22212131+111116n PP PP PP +++<.……………………………………………………………14分 20.(本小题满分14分)解:(1)方法一:设圆C的方程为:()222x a y r -+=()0r >, (1)分因为圆C 过点()0,0和()1,1-, 所以()22222,11.a r a r ⎧=⎪⎨--+=⎪⎩………………………………………………………………………………3分 解得1a =-,1r =.数学(理科)试题A 第 20 页 共 29 页所以圆C的方程为()2211x y ++=.…………………………………………………………………4分方法二:设()0,0O ,()1,1A -,依题意得,圆C 的圆心为线段OA 的垂直平分线l 与x 轴的交点C . (1)分 因为直线l的方程为1122y x -=+,即1y x =+,……………………………………………………2分 所以圆心C的坐标为()1,0-.…………………………………………………………………………3分 所以圆C的方程为()2211x y ++=.…………………………………………………………………4分(2)方法一:设圆D 上的动点P 的坐标为()00,x y , 则()220044x y -+=, 即()2200440y x =--≥, 解得026x ≤≤.…………………………………………………………………………………………5分由圆C 与圆D 的方程可知,过点P 向圆C 所作两条切线的斜率必存在,数学(理科)试题A 第 21 页 共 29 页设PA 的方程为:()010y y k x x -=-, 则点A 的坐标为()0100,y k x -, 同理可得点B 的坐标为()0200,y k x -, 所以120AB k k x =-,因为PA ,PB 是圆C 的切线,所以1k ,2k1=,即1k ,2k 是方程()()2220000022110x x k y x k y +-++-=的两根,………………………………7分即()0012200201220021,21.2y x k k x x y k k x x ⎧++=⎪+⎪⎨-⎪=⎪+⎩所以120AB k k x =-x =……………………………………………9分因为()220044y x =--, 所以AB =………………10分 设()()0020562x f x x -=+,则()()00305222x f x x -+'=+.……………………………………………………………数学(理科)试题A 第 22 页 共 29 页…………………11分由026x ≤≤,可知()0f x 在222,5⎡⎫⎪⎢⎣⎭上是增函数,在22,65⎛⎤⎥⎝⎦上是减函数,……………………12分所以()0max 2225564f x f ⎛⎫==⎡⎤ ⎪⎣⎦⎝⎭, ()()(){}min0131min 2,6min ,484f x f f ⎧⎫===⎡⎤⎨⎬⎣⎦⎩⎭, 所以AB的取值范围为⎦.…………………………………………………………………14分方法二:设圆D 上的动点P 的坐标为()00,x y , 则()220044x y -+=, 即()2200440y x =--≥, 解得026x ≤≤.…………………………………………………………………………………………5分 设点()0,A a ,()0,B b ,则直线PA :00y a y a x x --=,即()0000y a x x y ax --+=,因为直线PA 与圆C1=,化简得()2000220x a y a x +--=. ① 同理得()2000220x b y b x +--=, ②数学(理科)试题A 第 23 页 共 29 页由①②知a,b为方程()2000220x x y x x +--=的两根,…………………………………………7分即00002,2.2y a b x x ab x ⎧+=⎪+⎪⎨-⎪=⎪+⎩所以AB a b =-===…………9分因为()220044y x =--, 所以AB =………………10分=.………………………………………………………………11分 令012t x =+,因为026x ≤≤,所以1184t ≤≤.所以AB ==,…………………………………数学(理科)试题A 第 24 页 共 29 页……12分 当532t =时,max AB =,当14t =时,min AB =所以AB的取值范围为4⎦.…………………………………………………………………14分21.(本小题满分14分) (1)解法一:因为函数()ln f x a x =-11x x -+在区间()0,1内是增函数, 所以()()2201a f x x x '=-≥+()01x <<.……………………………………………………………1分即()2120a x x +-≥()01x <<, 即()221xa x ≥+……………………………………………………………………………………………2分212x x =++()01x <<, 因为21122x x<++在()0,1x ∈内恒成立,所以12a ≥.故实数a的取值范围为数学(理科)试题A 第 25 页 共 29 页1,2⎡⎫+∞⎪⎢⎣⎭.……………………………………………………………………4分解法二:因为函数()ln f x a x =-11x x -+在区间()0,1内是增函数, 所以()()2201a f x x x '-+≥=()01x <<.……………………………………………………………1分即()2120a x x +-≥()01x <<, 即()2210ax a x a +-+≥()01x <<,…………………………………………………………………2分设()()221g x ax a x a =+-+,当0a =时,得20x -≥,此时不合题意.当0a <时,需满足()()00,10,g g ≥⎧⎪⎨≥⎪⎩即()0,210,a a a a ≥⎧⎪⎨+-+≥⎪⎩解得12a ≥,此时不合题意.当0a >时,需满足()222140a a --≤⎡⎤⎣⎦或()()00,10,10,g g a a ⎧⎪≥⎪≥⎨⎪-⎪-<⎩或()()00,10,11,g g a a ⎧⎪≥⎪≥⎨⎪-⎪->⎩解得12a ≥或1a >,所以12a ≥.综上所述,实数a的取值范围为数学(理科)试题A 第 26 页 共 29 页1,2⎡⎫+∞⎪⎢⎣⎭.……………………………………………………………4分(2)证明:因为函数()e x g x =,所以()e x g x '=. 过点(),e b P b ,(),e b Q b --作曲线C 的切线方程为:1l :()e e b b y x b =-+, 2l :()e e b b y x b --=++,因为1l 与2l 的交点为()00,M x y , 由()()e e ,e e ,b b b by x b y x b --⎧=-+⎪⎨=++⎪⎩ ………………………………………………………………………………6分消去y,解得()()()0e +e e e eeb b b b bbb x -----=-. ①…………………………………………7分下面给出判定00x >的两种方法: 方法一:设e b t =,………………………………………………………………………………………8分因为0b >,所以1t >,且ln b t =. 所以()()2202+1ln 11t t t x t --=-.…………………………………………………………………………9分数学(理科)试题A 第 27 页 共 29 页设()()()22+1ln 1h t t t t =--()1t >, 则()12ln h t t t t t'=-+()1t >.………………………………………………………………………10分令()12ln u t t t t t=-+()1t >,则()212ln 1u t t t '=+-. 当1t >时,ln 0t >,2110t->,所以()212ln 10u t t t '=+->,………………………………11分所以函数()u t 在()1,+∞上是增函数, 所以()()10u t u >=,即()0h t '>, (12)分所以函数()h t 在()1,+∞上是增函数, 所以()()10h t h >=.…………………………………………………………………………………13分因为当1t >时,210t ->, 所以()()2202+1ln 101t t t x t --=>-.…………………………………………………………………14分方法二:由①得0x ()221+e 11e b bb --=--.数学(理科)试题A 第 28 页 共 29 页设2e b t -=,…………………………………………………………………………………………………8分因为0b >,所以01t <<,且ln 2t b =-. 于是21ln bt-=,……………………………………………………………………………………………9分所以()01+221ln 1ln 1b t b t x b t t t t +⎛⎫=+=+ ⎪--⎝⎭.…………………………………………………………10分由(1)知当12a =时,()1ln 2f x x =-11x x -+在区间()0,1上是增函数,…………………………11分所以()ln 2t f t =-()1101t f t -<=+, 即ln 2t <11t t -+. …………………………………………………………………………………………12分即210ln 1t t t++>-,………………………………………………………………………………………13分已知0b >, 所以数学(理科)试题A 第 29 页 共 29 页0210ln 1t x b t t +⎛⎫=+> ⎪-⎝⎭.…………………………………………………………………………14分。

2017年广州市普通高中毕业班综合测试广州二测广州市二测答案(理科数学)

2017年广州市普通高中毕业班综合测试广州二测广州市二测答案(理科数学)

数学答案(理科)试题B 第 1 页 共 11 页绝密 ★ 启用前2017年广州市普通高中毕业班综合测试(二)理科数学试题答案及评分参考评分说明:1.本解答给出了一种或几种解法供参考,如果考生的解法与本解答不同,可根据试题的主要考查内容比照评分参考制订相应的评分细则.2.对计算题,当考生的解答在某一步出现错误时,如果后继部分的解答未改变该题的内容和难度,可视影响的程度决定后继部分的给分,但不得超过该部分正确解答应得分数的一半;如果后继部分的解答有较严重的错误,就不再给分.3.解答右端所注分数,表示考生正确做到这一步应得的累加分数.4.只给整数分数.选择题不给中间分.一.选择题(1)A (2)B (3)A (4)B (5)A (6)C (7)D (8)C(9)B(10)C(11)B(12)D二.填空题 (13)32(14)23 (15)2590- (16)27三.解答题(17)解:(Ⅰ)因为数列{}n a 是等比数列,所以2132a a a =.因为1238a a a =,所以32=8a ,解得22=a .…………………………………………………………1分 因为()1253123-++++=n n a a a a S ,所以123a S =,即1213a a a =+.………………………………………………………………………2分 因为22=a ,所以11=a .………………………………………………………………………………3分 因为等比数列{}n a 的公比为212a q a ==, 所以数列{}n a 的通项公式为12-=n n a .…………………………………………………………………4分数学答案(理科)试题B 第 2 页 共 11 页(Ⅱ)因为等比数列{}n a 的首项为11=a ,公比2q =,所以()122121111-=--=--=n nn n q q a S .…………………………………………………………………6分因为n n b nS =,所以()212n nn b n n n =-=⋅-.………………………………………………………7分所以n n n b b b b b T +++++=-1321()()231222322123n n n =⨯+⨯+⨯++⨯-++++.…………………………………8分设231222322n n P n =⨯+⨯+⨯++⨯, 则234+121222322n n P n =⨯+⨯+⨯++⨯.所以()+1234222222n n n P n =⨯-+++++()1=122n n +-+.…………………………………10分因为()11232n n n +++++=, ……………………………………………………………………11分所以()()111222n n n n T n ++=-+-. 所以数列{}n b 的前n 项和()()111222n n n n T n ++=-+-.…………………………………………12分(18)(Ⅰ)证明:连接BD ,因为ABCD 是菱形,所以BD AC ⊥.……………………1分因为⊥FD 平面ABCD ,⊂AC 平面ABCD ,所以FD AC ⊥.………………………………………………2分因为D FD BD = ,所以⊥AC 平面BDF .……………3分 因为⊥EB 平面ABCD ,⊥FD 平面ABCD ,所以//EB FD .所以B ,D ,F ,E 四点共面.………………………………………………………………………4分 因为⊂EF 平面BDFE ,所以AC EF ⊥.……………………………………………………………5分FEDCB数学答案(理科)试题B 第 3 页 共 11 页(Ⅱ)解法1:如图,以D 为坐标原点,分别以DC ,DF 的方向 为y 轴,z 轴的正方向,建立空间直角坐标系xyz D -.……6分可以求得⎪⎪⎭⎫⎝⎛-0,21,23a a A ,⎪⎪⎭⎫ ⎝⎛0,21,23a a B ,⎪⎪⎭⎫⎝⎛a F 23,0,0, ()0,,0a C ,⎪⎪⎭⎫⎝⎛a a a E 3,21,23.………………………………7分 所以()0,,0a AB =,⎪⎪⎭⎫ ⎝⎛-=a a a 23,21,23.……………………………………………………8分设平面ABF 的法向量为()z y x ,,=n ,则⎪⎩⎪⎨⎧=∙=∙,0,0n n即0,10,2ay ay =⎧⎪⎨+=⎪⎩ 不妨取1x =,则平面ABF 的一个法向量为()1,0,1=n .……………………………………………10分 因为⎪⎪⎭⎫⎝⎛-=a a a 3,21,23, 所以36cos ,8CE CE CE∙==n n n . 所以直线CE 与平面ABF .…………………………………………………12分 解法2:如图,设ACBD O =,以O 为坐标原点,分别以OA ,OB 的方向为x 轴,y轴的正方向,建立空间直角 坐标系O xyz -.…………………………………………6分可以求得,0,02A a ⎛⎫⎪ ⎪⎝⎭,10,,02B a ⎛⎫ ⎪⎝⎭,,0,02C a ⎛⎫- ⎪ ⎪⎝⎭, 10,2E a ⎛⎫ ⎪⎝⎭,10,2F a ⎛⎫- ⎪ ⎪⎝⎭ (7)分数学答案(理科)试题B 第 4 页 共 11 页所以1,,02AB a ⎛⎫=- ⎪ ⎪⎝⎭,1,2AF a ⎛⎫=-- ⎪ ⎪⎝⎭.………………………………………8分设平面ABF 的法向量为()z y x ,,=n ,则⎪⎩⎪⎨⎧=∙=∙,0,0ABn n即10,210,2ay ay ⎧+=⎪⎪⎨⎪-+=⎪⎩不妨取1x=,则平面ABF 的一个法向量为()=n .………………………………………10分因为31,2CE a ⎛⎫= ⎪⎪⎝⎭,所以36cos ,CE CE CE∙==n n n .所以直线CE 与平面ABF 所成角的正弦值为8.…………………………………………………12分 (说明:若本题第(Ⅰ)问采用向量法证明正确,第(Ⅰ)问给6分,仍将建系、写点的坐标与向量的坐标等分值给到第(Ⅱ)问)(19)解:(Ⅰ)依题意,1ξ的所有取值为68.1,92.1,1.2,4.2,…………………………………1分 因为()30.05.06.068.11=⨯==ξP ,()30.05.06.092.11=⨯==ξP ,()20.05.04.01.21=⨯==ξP ,()20.05.04.04.21=⨯==ξP .………………………………3分 所以1ξ的分布列为依题意,2ξ的所有取值为68.1,8.1,24.2,4.2,…………………………………………………5分 因为()42.06.07.068.12=⨯==ξP ,()18.06.03.08.12=⨯==ξP ,()28.04.07.024.22=⨯==ξP ,()12.04.03.04.22=⨯==ξP ,……………………………7分……………4分数学答案(理科)试题B 第 5 页 共 11 页所以2ξ的分布列为(Ⅱ)令i Q 表示方案i 所带来的利润,则所以1150.30+200.50+250.20=19.5EQ =⨯⨯⨯, 2150.42+200.46+250.12=18.5EQ =⨯⨯⨯. 因为12EQ EQ >,所以实施方案1,第二个月的利润更大.………………………………………………………………12分(20)解:(Ⅰ)双曲线2215x y -=的焦点坐标为(),离心率为5.………………………1分因为双曲线2215x y -=的焦点是椭圆C :22221x y a b+=()0a b >>的顶点,且椭圆与双曲线的离心率 互为倒数,所以a ==,解得1b =. 故椭圆C 的方程为1622=+y x .…………………………………………………………………………3分 (Ⅱ)因为2334>=MN ,所以直线MN 的斜率存在.………………………………………………4分 因为直线MN 在y 轴上的截距为m ,所以可设直线MN 的方程为m kx y +=.……………8分…………………………10分……………………………9分数学答案(理科)试题B 第 6 页 共 11 页代入椭圆方程1622=+y x 得0)1(612)61(222=-+++m kmx x k .…………………………………5分 因为()0)61(24)1)(61(241222222>-+=-+-=∆m k m k km ,所以2261k m +<.………………………………………………………………………………………6分 设),(11y x M ,),(22y x N ,根据根与系数的关系得1221216kmx x k -+=+,()21226116m x x k-=+.……………………………………7分 则()212212212411x x x x kx x k MN -++=-+== 因为334=MN ,.………………………………8分 整理得()22421973918kk k m +++-=.………………………………………………………………………9分 令112≥=+t k ,则12-=t k .所以2218755015075230575189993t t m t t t -+-⎡⎤-⨯⎛⎫==-+≤= ⎪⎢⎥⎝⎭⎣⎦.…………………………10分等号成立的条件是35=t ,此时322=k ,253m =满足2261k m +<,符合题意.………………11分故m 的最大值为315.…………………………………………………………………………………12分(21)解:(Ⅰ)函数()f x 的定义域为()()0,11,+∞.因为()f x ln x ax b x =-+,所以()f x '2ln 1ln x a x-=-.…………………………………………1分 所以函数()f x 在点()()e,e f 处的切线方程为()()e e e y a b a x --+=--,即e y ax b =-++.………………………………………………2分已知函数()f x 在点()()e,e f 处的切线方程为2e y ax =-+,比较求得e b =.所以实数b 的值为e .……………………………………………………………………………………3分数学答案(理科)试题B 第 7 页 共 11 页(Ⅱ)解法1:由()f x 1e 4?,即1e e ln 4x ax x -+?.……………………………………………4分 所以问题转化为11ln 4a x x ≥-在2e,e 轾犏臌上有解.………………………………………………………5分 令()11ln 4h x x x=-()2e,e x 轾Î犏臌, 则()h x '22114ln x x x =-222ln 44ln x x x x-=(22ln ln 4ln x x x x +-=.………………………………7分 令()ln p x x =-,所以当2e,e x 轾Î犏臌时,有()110p x xx'==<.……………………………………………8分 所以函数()p x 在区间2e,e 轾犏臌上单调递减.……………………………………………………………9分 所以()()e ln e 0p x p <=-<. ………………………………………………………………10分所以()0h x '<,即()h x 在区间2e,e 轾犏臌上单调递减. ………………………………………………11分 所以()()22221111eln e4e 24e h x h ≥=-=-. 所以实数a 的取值范围为211,24e轹÷ê-+?÷÷êøë.…………………………………………………………12分 解法2:命题“存在x Î2e,e 轾犏臌,满足()f x 1e 4?”等价于“当x Î2e,e 轾犏臌时,有()min f x ⎡⎤⎣⎦1e 4?”.………………………………………4分由(Ⅰ)知,()f x '2ln 1ln x a x -=-=2111ln 24a x 骣÷ç--+-÷ç÷ç桫. (1)当14a ³时,()0f x '≤,即函数()f x 在区间2e,e 轾犏臌上为减函数,…………………………5分 所以()minf x =⎡⎤⎣⎦()2e f 22e e e 2a =-+.由()min f x ⎡⎤⎣⎦1e 4?,得22e 1e e e 24a -+?,解得21124e a ?. 所以21124e a ?.………………………………………………………………………………………6分数学答案(理科)试题B 第 8 页 共 11 页(2)当14a <时,注意到函数()f x '=2111ln 24a x 骣÷ç--+-÷ç÷ç桫在区间2e,e 轾犏臌上的值域为1,4a a 轾犏--犏臌. ……………………………………7分①0a £,()0f x '≥在区间2e,e 轾犏臌上恒成立,即函数()f x 在区间2e,e 轾犏臌上为增函数. 所以()()min e f x f =⎡⎤⎣⎦e e e =2e e a a =-+-.由于()min f x ≤⎡⎤⎣⎦1e 4+,所以2e e a -?1e 4+,解得1104e a ≥->,这与0a ≤矛盾.………8分 ②若104a <<,由函数()f x '的单调性(单调递增)和值域知,存在唯一的()20e,e x ∈,使()00f x '=,且满足当x Î()0e,x 时,()00f x '<,即()f x 为减函数;当x Î()0,e x 时,()00f x '>,即()f x 为增函数.所以()()0min f x f x =⎡⎤⎣⎦000e ln x ax x =-+.…………………………………………………………9分 由()min f x ≤⎡⎤⎣⎦1e 4+,得000e ln x ax x -+?1e 4+,即0001ln 4x ax x -?. 因为()00f x '=,即020ln 10ln x a x --=,所以02ln 1ln x a x -=. 将02ln 1ln x a x -=代入0001ln 4x ax x -?,得0201ln 4x x £,其中()20e,e x ∈.………………………10分 令()h x 2ln x x =,则()h x '3ln 2ln x x-=, 当x Î2e,e 轾犏臌时,()0h x '≤,即()h x 在区间2e,e 轾犏臌上为减函数.所以()()2eh x h ≥()2222e e 1>44ln e ==,与0201ln 4x x £矛盾, 所以不存在10,4a ⎛⎫∈ ⎪⎝⎭,使()min f x ≤⎡⎤⎣⎦1e 4+成立.………………………………………………11分综上可知,实数a 的取值范围为211,24e轹÷ê-+?÷÷êøë.…………………………………………………12分 (说明:当104a <<时,也可转化为200ln 4x x ≥,其中()20e,e x ∈,从而构造函数()2ln x p x x =解答;还可数学答案(理科)试题B 第 9 页 共 11 页转化为0011ln 4a x x ?,从而构造函数()11ln 4q x x x =-解答;还有其他解法均参照给分!)(22)(Ⅰ)解:曲线C 的普通方程为141222=+y x .……………………………………………………1分 将直线02=--y x 代入141222=+y x 中消去y 得,032=-x x .…………………………………2分 解得0=x 或3=x .………………………………………………………………………………………3分 所以点()2,0-A ,()1,3B ,………………………………………………………………………………4分 所以()()23210322=++-=AB .………………………………………………………………5分(Ⅱ)解法1:在曲线C 上求一点P , 使△PAB 的面积最大,则点P 到直线l 的距离最大.设过点P 且与直线l 平行的直线方程为b x y +=.……………………………………………………6分将b x y +=代入141222=+y x 整理得,()0436422=-++b bx x . 令()()22644340b b ∆=-⨯⨯-=,解得4±=b .…………………………………………………7分将4±=b 代入方程()0436422=-++b bx x ,解得3±=x .易知当点P 的坐标为()1,3-时,△PAB 的面积最大.………………………………………………8分 且点P ()1,3-到直线l 的距离为231121322=+---=d .……………………………………………9分△PAB 的最大面积为=⨯⨯=d AB S 219.…………………………………………………………10分 解法2:在曲线C 上求一点P , 使△PAB 的面积最大,则点P 到直线l 的距离最大.设曲线C 上点()θθsin 2,cos 32P ,其中[)π2,0∈θ,………………………………………………6分则点P 到直线l 的距离为22112sin 2cos 32+--=θθd 226πcos 4-⎪⎭⎫ ⎝⎛+=θ.………………………8分 因为[)π2,0∈θ,则6π136π6π<+≤θ, 所以当π6π=+θ,即65π=θ时,23max =d .………………………………………………………9分此时点P 的坐标为()1,3-,△PAB 的最大面积为=⨯⨯=d AB S 219.…………………………10分数学答案(理科)试题B 第 10 页 共 11 页(23)(Ⅰ)证明1:因为1=++c b a ,所以()()()222111+++++c b a ()32222++++++=c b a c b a 5222+++=c b a .所以要证明()()()316111222≥+++++c b a , 即证明31222≥++c b a .…………………………………………………………………………………1分 因为()()ca bc ab c b a c b a ++-++=++22222 ……………………………………………………2分 ()()22222c b a c b a ++-++≥,……………………………………………………3分所以()()22223c b a c b a ++≥++.……………………………………………………………………4分因为1=++c b a ,所以31222≥++c b a . 所以()()()316111222≥+++++c b a .…………………………………………………………………5分 证明2:因为1=++c b a ,所以()()()222111+++++c b a ()32222++++++=c b a c b a 5222+++=c b a .所以要证明()()()316111222≥+++++c b a , 即证明31222≥++c b a .…………………………………………………………………………………1分 因为21293a a +≥,21293b b +≥,21293c c +≥,……………………………………………………3分 所以()2221233a b c a b c +++≥++.…………………………………………………………………4分因为1=++c b a ,所以31222≥++c b a . 所以()()()316111222≥+++++c b a .…………………………………………………………………5分 证明3:因为()()21681193a a ++≥+,()()21681193b b ++≥+,()()21681193c c ++≥+, ……………………………3分所以()()()()()()22216811111133a b c a b c ++++++≥+++++⎡⎤⎣⎦.……………………………4分数学答案(理科)试题B 第 11 页 共 11 页 因为1=++c b a ,所以()()()316111222≥+++++c b a .…………………………………………………………………5分 (Ⅱ)解:设()12-+-=x a x x f ,则“对任意实数x ,不等式+212x a x --≥恒成立”等价于“()min 2f x ≥⎡⎤⎣⎦”.…………6分 当21<a 时,()⎪⎪⎪⎩⎪⎪⎪⎨⎧>--≤≤-+-<++-=.21,13,21,1,,13x a x x a a x a x a x x f 此时()min 11=22f x f a ⎛⎫=-⎡⎤ ⎪⎣⎦⎝⎭, 要使+212x a x --≥恒成立,必须221≥-a ,解得23-≤a .……………………………………7分 当21=a 时,3221≥-x 不可能恒成立.………………………………………………………………8分 当21>a 时,()⎪⎪⎪⎩⎪⎪⎪⎨⎧>--≤≤-+<++-=.,13,21,1,21,13a x a x a x a x x a x x f 此时()min 11=22f x f a ⎛⎫=-⎡⎤ ⎪⎣⎦⎝⎭, 要使+212x a x --≥恒成立,必须221≥-a ,解得25≥a .……………………………………9分 综上可知,实数a 的取值范围为⎪⎭⎫⎢⎣⎡+∞⎥⎦⎤⎝⎛-∞-,2523, .……………………………………………10分。

(完整版)2017届广州市普通高中毕业班综合测试(一)(理数)试题及答案,推荐文档

(完整版)2017届广州市普通高中毕业班综合测试(一)(理数)试题及答案,推荐文档

2017届广州市普通高中毕业班综合测试(一)数学(理科)本试卷共4页,23小题, 满分150分。

考试用时120分钟。

注意事项:1.本试卷分第Ⅰ卷(选择题)和第Ⅱ卷(非选择题)两部分.答卷前,考生务必将自己的姓名、准考证号填写在答题卡上.2.回答第Ⅰ卷时,选出每小题答案后,用铅笔把答题卡上对应题目的答案标号涂黑.如需改动,用橡皮擦干净后,再选涂其它答案标号.写在本试卷上无效.3.回答第Ⅱ卷时,将答案写在答题卡上,写在本试卷上无效. 4.考试结束后,将本试卷和答题卡一并交回.第Ⅰ卷一、选择题:本小题共12题,每小题5分,在每小题给出的四个选项中,只有一项是符合 题目要求的。

(1)复数()221i 1i+++的共轭复数是 (A )1i + (B )1i - (C )1i -+ (D )1i -- (2)若集合}{1M x x =≤,}{2,1N y y x x ==≤,则(A )M N = (B )M N ⊆ (C )N M ⊆ (D )M N =∅I (3)已知等比数列{}n a 的各项都为正数, 且35412a ,a ,a 成等差数列,则3546a a a a ++的值是(A 51- (B 51+ (C )35- (D 35+ (4)阅读如图的程序框图. 若输入5n =, 则输出k 的值为(A )2 (B )3 (C )4 (D )5(5)已知双曲线C 222:14x y a -=的一条渐近线方程为230+=x y ,1F ,2F 分别 是双曲线C 的左,右焦点, 点P 在双曲线C 上, 且17PF =, 则2PF 等于 (A )1 (B )13 (C )4或10 (D )1或13(6)如图, 网格纸上小正方形的边长为1, 粗线画出的是某几何体的正视图(等腰直角三角形)和侧视图,且该几何体的体积为83, 则该几何体的俯视图可以是(7)五个人围坐在一张圆桌旁,每个人面前放着完全相同的硬币,所有人同时翻转自己的硬币. 若硬币正面朝上, 则这个人站起来; 若硬币正面朝下, 则这个人继续坐着. 那么, 没有相邻的两个人站起来的概率为(A)12(B)1532(C)1132(D)516(8)已知1F,2F分别是椭圆C()2222:10x ya ba b+=>>的左, 右焦点, 椭圆C上存在点P使12F PF∠为钝角, 则椭圆C的离心率的取值范围是(A)22⎛⎫⎪⎪⎝⎭(B)1,12⎛⎫⎪⎝⎭(C)20,2⎛⎝⎭(D)10,2⎛⎫⎪⎝⎭(9)已知:0,1xp x e ax∃>-<成立, :q函数()()1xf x a=--在R上是减函数, 则p是q的(A)充分不必要条件(B)必要不充分条件(C)充要条件(D)既不充分也不必要条件(10)《九章算术》中,将底面为长方形且有一条侧棱与底面垂直的四棱锥称之为阳马;将四个面都为直角三角形的三棱锥称之为鳖臑.若三棱锥-P ABC为鳖臑, PA⊥平面ABC, 2PA AB==,4AC=, 三棱锥-P ABC的四个顶点都在球O的球面上, 则球O的表面积为(A)8π(B)12π(C)20π(D)24π(11)若直线1y=与函数()2sin2f x x=的图象相交于点()11,P x y,()22,Q x y,且12x x-=23π,则线段PQ与函数()f x的图象所围成的图形面积是(A)233π+(B)33π+(C)2323π+(D)323π(12)已知函数()32331248f x x x x=-++, 则201612017kkf=⎛⎫⎪⎝⎭∑的值为(A)0(B)504(C)1008(D)2016P CBA第Ⅱ卷本卷包括必考题和选考题两部分。

2017届广州市一般高中毕业班综合测试(一)(理数)试题及答案

2017届广州市一般高中毕业班综合测试(一)(理数)试题及答案

2017届广州市一般高中毕业班综合测试(一)数学(理科)本试卷共4页,23小题, 总分值150分。

考试历时120分钟。

注意事项:1.本试卷分第Ⅰ卷(选择题)和第Ⅱ卷(非选择题)两部份.答卷前,考生务必将自己的姓名、准考证号填写在答题卡上.2.回答第Ⅰ卷时,选出每题答案后,用铅笔把答题卡上对应题目的答案标号涂黑.如需改动,用橡皮擦干净后,再选涂其它答案标号.写在本试卷上无效.3.回答第Ⅱ卷时,将答案写在答题卡上,写在本试卷上无效. 4.考试终止后,将本试卷和答题卡一并交回.第Ⅰ卷一、选择题:本小题共12题,每题5分,在每题给出的四个选项中,只有一项为哪一项符合题目要求的。

(1)复数()221i 1i+++的共轭复数是 (A )1i + (B )1i - (C )1i -+ (D )1i -- (2)假设集合}{1M x x =≤,}{2,1N y y x x ==≤,那么(A )M N = (B )M N ⊆ (C )N M ⊆ (D )M N =∅(3)已知等比数列{}n a 的各项都为正数, 且35412a ,a ,a 成等差数列,则3546a a a a ++的值是(A 51- (B 51+ (C )35- (D 35+ (4)阅读如图的程序框图. 假设输入5n =, 那么输出k 的值为(A )2 (B )3 (C )4 (D )5(5)已知双曲线C222:14x ya-=的一条渐近线方程为230+=x y,1F,2F别离是双曲线C的左,右核心, 点P在双曲线C上, 且17PF=, 则2PF等于(A)1(B)13(C)4或10(D)1或13(6)如图, 网格纸上小正方形的边长为1, 粗线画出的是某几何体的正视图(等腰直角三角形)和侧视图,且该几何体的体积为83, 那么该几何体的俯视图能够是(7)五个人围坐在一张圆桌旁,每一个人眼前放着完全相同的硬币,所有人同时翻转自己的硬币. 假设硬币正面朝上, 那么那个人站起来; 假设硬币正面朝下, 那么那个人继续坐着. 那么, 没有相邻的两个人站起来的概率为(A )12 (B )1532 (C )1132(D )516 (8)已知1F ,2F 别离是椭圆C ()2222:10x y a b a b+=>>的左, 右核心, 椭圆C 上存在点P 使12F PF ∠为钝角, 那么椭圆C 的离心率的取值范围是(A )22⎛⎫⎪ ⎪⎝⎭ (B )1,12⎛⎫ ⎪⎝⎭ (C )20,2⎛⎫ ⎪ ⎪⎝⎭(D )10,2⎛⎫⎪⎝⎭ (9)已知:0,1xp x e ax ∃>-<成立, :q 函数()()1xf x a =--在R 上是减函数, 则p 是q 的(A )充分没必要要条件 (B )必要不充分条件 (C )充要条件 (D )既不充分也没必要要条件 (10)《九章算术》中,将底面为长方形且有一条侧棱与底面垂直的四棱锥称之为阳马;将四 个面都为直角三角形的三棱锥称之为鳖臑.假设三棱锥-P ABC 为鳖臑, PA ⊥平面ABC , 2PA AB ==,4AC =, 三棱锥-P ABC 的四个极点都在球O 的球面上,那么球O 的表面积为(A )8π (B )12π (C )20π (D )24π (11)假设直线1y =与函数()2sin 2f x x =的图象相交于点()11,P x y ,()22,Q x y ,且12x x -=23π,那么线段PQ 与函数()f x 的图象所围成的图形面积是 (A )233π+ (B )33π+ (C ) 2323π+ (D )323π (12)已知函数()32331248f x x x x =-++, 则201612017k k f =⎛⎫⎪⎝⎭∑的值为 (A ) 0 (B )504 (C )1008 (D )2016P CBA第Ⅱ卷本卷包括必考题和选考题两部份。

2017届广州市普通高中毕业班综合测试(一)(理数)

2017届广州市普通高中毕业班综合测试(一)(理数)

2017届广州市普通高中毕业班综合测试(一)数学(理科)本试卷共4页,23小题, 满分150分。

考试用时120分钟。

注意事项:1.本试卷分第Ⅰ卷(选择题)和第Ⅱ卷(非选择题)两部分.答卷前,考生务必将自己的姓名、准考证号填写在答题卡上.2.回答第Ⅰ卷时,选出每小题答案后,用铅笔把答题卡上对应题目的答案标号涂黑.如需改动,用橡皮擦干净后,再选涂其它答案标号.写在本试卷上无效.3.回答第Ⅱ卷时,将答案写在答题卡上,写在本试卷上无效. 4.考试结束后,将本试卷和答题卡一并交回.第Ⅰ卷一、选择题:本小题共12题,每小题5分,在每小题给出的四个选项中,只有一项是符合 题目要求的。

(1)复数()221i 1i+++的共轭复数是 (A )1i + (B )1i - (C )1i -+ (D )1i -- (2)若集合}{1M x x =≤,}{2,1N y y x x ==≤,则(A )M N = (B )M N ⊆ (C )N M ⊆ (D )M N =∅(3)已知等比数列{}n a 的各项都为正数, 且35412a ,a ,a 成等差数列,则3546a a a a ++的值是(A )512- (B )512+ (C )352- (D )352+ (4)阅读如图的程序框图. 若输入5n =, 则输出k 的值为(A )2 (B )3 (C )4 (D )5(5)已知双曲线C 222:14x y a -=的一条渐近线方程为230+=x y ,1F ,2F 分别 是双曲线C 的左,右焦点, 点P 在双曲线C 上, 且17PF =, 则2PF 等于 (A )1 (B )13 (C )4或10 (D )1或13(6)如图, 网格纸上小正方形的边长为1, 粗线画出的是某几何体的正视图(等腰直角三角形)和侧视图,且该几何体的体积为83, 则该几何体的俯视图可以是(7)五个人围坐在一张圆桌旁,每个人面前放着完全相同的硬币,所有人同时翻转自己的硬币. 若硬币正面朝上, 则这个人站起来; 若硬币正面朝下, 则这个人继续坐着. 那么, 没有相邻的两个人站起来的概率为(A)12(B)1532(C)1132(D)516(8)已知1F,2F分别是椭圆C()2222:10x ya ba b+=>>的左, 右焦点, 椭圆C上存在点P使12F PF∠为钝角, 则椭圆C的离心率的取值范围是(A)2,12⎛⎫⎪⎪⎝⎭(B)1,12⎛⎫⎪⎝⎭(C)20,2⎛⎫⎪⎪⎝⎭(D)10,2⎛⎫⎪⎝⎭(9)已知:0,1xp x e ax∃>-<成立, :q函数()()1xf x a=--在R上是减函数, 则p是q的(A)充分不必要条件(B)必要不充分条件(C)充要条件(D)既不充分也不必要条件(10)《九章算术》中,将底面为长方形且有一条侧棱与底面垂直的四棱锥称之为阳马;将四个面都为直角三角形的三棱锥称之为鳖臑.若三棱锥-P ABC为鳖臑, PA⊥平面ABC, 2PA AB==,4AC=, 三棱锥-P ABC的四个顶点都在球O的球面上, 则球O的表面积为(A)8π(B)12π(C)20π(D)24π(11)若直线1y=与函数()2sin2f x x=的图象相交于点()11,P x y,()22,Q x y,且12x x-=23π,则线段PQ与函数()f x的图象所围成的图形面积是(A)233π+(B)33π+(C)2323π+-(D)323π+-(12)已知函数()32331248f x x x x=-++, 则201612017kkf=⎛⎫⎪⎝⎭∑的值为(A)0(B)504(C)1008(D)2016P CBA第Ⅱ卷本卷包括必考题和选考题两部分。

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2017届市普通高中毕业班综合测试(二)数学(理科)本试卷共4页,23小题, 满分150分。

考试用时120分钟。

注意事项:1.本试卷分第Ⅰ卷(选择题)和第Ⅱ卷(非选择题)两部分.答卷前,考生务必将自己的、号填写在答题卡上.2.回答第Ⅰ卷时,选出每小题答案后,用铅笔把答题卡上对应题目的答案标号涂黑.如需改动,用橡皮擦干净后,再选涂其它答案标号.写在本试卷上无效.3.回答第Ⅱ卷时,将答案写在答题卡上,写在本试卷上无效. 4.考试结束后,将本试卷和答题卡一并交回.第Ⅰ卷(共60分)一、选择题:本大题共12个小题,每小题5分,共60分.在每小题给出的四个选项中,只有一项是符合题目要求的.1.已知集合{}11A x x =-<,110B x x ⎧⎫=-≥⎨⎬⎩⎭, 则A B =∩( )A .{}12x x ≤< B .{}02x x << C .{}01x x <≤ D .{}01x x << 2.若复数z 满足()34i i 2i z -+=+,则复数z 所对应的点位于( )A .第一象限B .第二象限C .第三象限D .第四象限3.执行如图所示的程序框图,则输出的S 值为( ) A .4 B .3 C .2- D .3-4.从1,2,3,4,5这5个数字中任取3个数字组成没有重复数字的三位数,则这个三位数是偶数的概率为( ) A .15 B .25 C .12 D .355.函数()()ln 1f x x x =-+的大致图象是( )6.已知2cos 423πθ⎛⎫-=⎪⎝⎭,则sin θ=( ) A .79 B .19 C .19- D .79-7.已知点()4,4A 在抛物线22y px =(()0p >)上,该抛物线的焦点为F ,过点A 作该抛物线准线的垂线,垂足为E ,则EAF ∠的平分线所在的直线方程为( ) A .2120x y +-= B .2120x y +-= C .240x y --= D .240x y -+=8.在棱长为2的正方体1111ABCD A B C D -中,M 是棱11A D 的中点,过1C ,B ,M 作正方体的截面,则这个截面的面积为( )A .352 B .358 C .92 D .989.已知R k ∈,点(),P a b 是直线2x y k +=与圆22223x y k k +=-+的公共点,则ab 的最大值为( )A .15B .9C .1D .53- 10.已知函数()2sin 4f x x πω⎛⎫=+⎪⎝⎭(0ω>)的图象在区间[]0,1上恰有3个最高点,则ω的取值围为( )A .1927,44ππ⎡⎫⎪⎢⎣⎭B .913,22ππ⎡⎫⎪⎢⎣⎭C .1725,44ππ⎡⎫⎪⎢⎣⎭D .[)4,6ππ 11.如图,网格纸上小正方形的边长为1,粗线画出的是某三棱锥的三视图,则该三棱锥的体积为( )A .83 B .163 C .323D .1612.定义在R 上的奇函数()y f x =为减函数,若m ,n 满足()22f m m -+()220f n n -≥,则当1n ≤32≤时,mn的取值围为( ) A .2,13⎡⎤-⎢⎥⎣⎦ B .31,2⎡⎤⎢⎥⎣⎦ C .13,32⎡⎤⎢⎥⎣⎦ D .1,13⎡⎤⎢⎥⎣⎦第Ⅱ卷(共90分)本卷包括必考题和选考题两部分。

第13~21题为必考题,每个考生都必须作答。

第22~23题为选考题,考生根据要求作答。

二、填空题:本小题共4题,每小题5分。

13.已知点()00O ,,()1,3A -,()24B -,,m +=2,若点P 在y 轴上,则实数m = . 14.《子算经》是我国古代重要的数学著作,约成书于四、五世纪,传本的《子算经》共三卷,其中下卷“物不知数”中有如下问题:“今有物,不知其数.三三数之,剩二;五五数之,剩三;七七数之,剩二.问:物几何?”其意思为:“现有一堆物品,不知它的数目.3个3个数,剩2个;5个5个数,剩3个;7个7个数,剩2个.问这堆物品共有多少个?”试计算这堆物品至少有 个. 15.设()()5423x y x y -+9872987a x a x y a x y =+++8910a xy a y ++,则08a a += .16.在平面四边形ABCD 中,连接对角线BD ,已知9CD =,16BD =,90BDC ∠=︒,4sin 5A =,则对角线AC 的最大值为 . 三、解答题 (本大题共6小题,共70分.解答应写出文字说明、证明过程或演算步骤.) 17.(本小题满分12分)设等比数列{}n a 的前n 项和n S ,已知1238a a a =,(2133n S a a =++)521n a a -+(*N n ∈).(Ⅰ)求数列{}n a 的通项公式;(Ⅱ)设n n b nS =,求数列{}n b 的前n 项和n T . 18.(本小题满分12分)如图,ABCD 是边长为a 的菱形,60BAD ∠=︒,EB ⊥平面ABCD ,FD ⊥平面ABCD ,23EB FD a ==.(Ⅰ)求证:EF AC ⊥;(Ⅱ)求直线CE 与平面ABF 所成角的正弦值.19.(本小题满分12分)某商场拟对某商品进行促销,现有两种方案供选择,每种促销方案都需分两个月实施,且每种方案中第一个月与第二个月的销售相互独立.根据以往促销的统计数据,若实施方案1,预计第一个月的销量是促销前的1.2倍和1.5倍的概率分别是0.6和0.4,第二个月的销量是第一个月的1.4倍和1.6倍的概率都是0.5;若实施方案2,预计第一个月的销量是促销前的1.4倍和1.5倍的概率分别是0.7和0.3,第二个月的销量是第一个月的1.2倍和1.6倍的概率分别是0.6和0.4.令()1,2i i ξ=表示实施方案i 的第二个月的销量是促销前销量的倍数.(Ⅰ)求1ξ,2ξ的分布列;(Ⅱ)不管实施哪种方案,i ξ与第二个月的利润之间的关系如下表,试比较哪种方案第二个月的利润更大.20.(本小题满分12分)已知双曲线2215x y -=的焦点是椭圆C :22221x y a b+=(0a b >>)的顶点,且椭圆与双曲线的离心率互为倒数.(Ⅰ)求椭圆C 的方程;(Ⅱ)设动点M ,N 在椭圆C 上,且43MN =MN 在y 轴上的截距为m ,求m 的最大值. 21.(本小题满分12分) 已知函数()ln xf x ax b x=-+在点()()e,e f 处的切线方程为2e y ax =-+. (Ⅰ)数b 的值;(Ⅱ)若存在2e,e x ⎡⎤∈⎣⎦,满足()1e 4f x ≤+,数a 的取值围. 请考生在22、23两题中任选一题作答,如果多做,则按所做的第一题记分. 22.(本小题满分10分)选修4-4:坐标系与参数方程在平面直角坐标系xOy 中,已知直线l 的普通方程为20x y --=,曲线C 的参数方程为23,2sin x y θθ⎧=⎪⎨=⎪⎩(θ为参数),设直线l 与曲线C 交于A ,B 两点.(Ⅰ)求线段AB 的长;(Ⅱ)已知点P 在曲线C 上运动,当PAB ∆的面积最大时,求点P 的坐标及PAB ∆的最大面积. 23.(本小题满分10分)选修4-5:不等式选讲 (Ⅰ)已知1a b c ++=,证明:()()2211a b ++++()21613c +≥; (Ⅱ)若对任意实数x ,不等式x a -+212x -≥恒成立,数a 的取值围.数学(理科)参考答案评分说明:1.本解答给出了一种或几种解法供参考,如果考生的解法与本解答不同,可根据试题的主要考查容比照评分参考制订相应的评分细则.2.对计算题,当考生的解答在某一步出现错误时,如果后继部分的解答未改变该题的容和难度,可视影响的程度决定后继部分的给分,但不得超过该部分正确解答应得分数的一半;如果后继部分的解答有较严重的错误,就不再给分.3.解答右端所注分数,表示考生正确做到这一步应得的累加分数. 4.只给整数分数.选择题不给中间分. 一.选择题(1)A (2)B (3)A (4)B (5)A (6)C (7)D (8)C (9)B (10)C (11)B (12)D 二.填空题 (13)32(14)23 (15)2590 (16)27 三.解答题(17)解:(Ⅰ)因为数列{}n a 是等比数列,所以2132a a a =.因为1238a a a =,所以32=8a ,解得22=a .…………………………………1分 因为()1253123-++++=n n a a a a S ,所以123a S =,即1213a a a =+.…………………………………………………2分 因为22=a ,所以11=a .…………………………………………………………3分 因为等比数列{}n a 的公比为212a q a ==, 所以数列{}n a 的通项公式为12-=n n a .……………………………………………4分(Ⅱ)因为等比数列{}n a 的首项为11=a ,公比2q =,所以()122121111-=--=--=n nn n q q a S .……………………………………………6分 因为n n b nS =,所以()212n nn b n n n =-=⋅-.…………………………………7分所以n n n b b b b b T +++++=-1321 ()()231222322123n n n =⨯+⨯+⨯++⨯-++++.………………8分设231222322n n P n =⨯+⨯+⨯++⨯,则234+121222322n n P n =⨯+⨯+⨯++⨯.所以()+1234222222n n n P n =⨯-+++++()1=122n n +-+.………………10分因为()11232n n n +++++=, …………………………………………………11分 所以()()111222n n n n T n ++=-+-. 所以数列{}n b 的前n 项和()()111222n n n n T n ++=-+-.………………12分 (18)(Ⅰ)证明:连接BD ,因为ABCD 是菱形,所以BD AC ⊥.……………………1分因为⊥FD 平面ABCD ,⊂AC 平面ABCD ,所以FD AC ⊥. (2)分因为D FD BD = ,所以⊥AC 平面BDF .……………3分因为⊥EB 平面ABCD ,⊥FD 平面ABCD ,所以//EB FD . 所以B ,D ,F ,E 四点共面.……………………………4分 因为⊂EF 平面BDFE ,所以AC EF ⊥.………………5分(Ⅱ)解法1:如图,以D 为坐标原点,分别以,DF 的方向 为y 轴,z 轴的正方向,建立空间直角坐标系xyz D -.……6分可以求得⎪⎪⎭⎫⎝⎛-0,21,23a a A ,⎪⎪⎭⎫ ⎝⎛0,21,23a a B ,⎪⎪⎭⎫⎝⎛a F 23,0,0,()0,,0a C ,⎪⎪⎭⎫ ⎝⎛a a a E 3,21,23.………………………………7分 所以()0,,0a =,⎪⎪⎭⎫ ⎝⎛-=a a a AF 23,21,23.……………………………………8分设平面ABF 的法向量为()z y x ,,=n ,则⎪⎩⎪⎨⎧=•=•,0,0n n 即0,10,222ay ax ay az =⎧⎪⎨-++=⎪⎩FEDCBA不妨取1x =,则平面ABF 的一个法向量为()1,0,1=n .…………………………10分 因为⎪⎪⎭⎫⎝⎛-=a a a CE 3,21,23, 所以36cos ,8CE CE CE•==n n n . 所以直线CE 与平面ABF 所成角的正弦值为8.……………………………12分 解法2:如图,设ACBD O =,以O 为坐标原点,分别以OA ,OB 的方向为x轴,y 轴的正方向,建立空间直角 坐标系O xyz -.…………………………………………6分可以求得,0,0A a ⎫⎪⎪⎝⎭,10,,02B a ⎛⎫ ⎪⎝⎭,,0,0C ⎛⎫ ⎪ ⎪⎝⎭,10,2E a ⎛⎫ ⎪⎝⎭,10,,22F a a ⎛⎫- ⎪ ⎪⎝⎭.………………7分 所以1,,022ABa a ⎛⎫=-⎪ ⎪⎝⎭,1,,222AF a a a ⎛⎫=-- ⎪ ⎪⎝⎭.……………………8分 设平面ABF 的法向量为()z y x ,,=n ,则⎪⎩⎪⎨⎧=•=•,0,0n n即10,210,2ay ay ⎧+=⎪⎪⎨⎪-=⎪⎩不妨取1x =,则平面ABF 的一个法向量为()=n .……………………10分 因为31,22CE a a ⎛⎫= ⎪⎪⎝⎭,所以36cos ,CE CE CE•==n n n所以直线CE 与平面ABF 所成角的正弦值为8.………………………………12分(说明:若本题第(Ⅰ)问采用向量法证明正确,第(Ⅰ)问给6分,仍将建系、写点的坐标与向量的坐标等分值给到第(Ⅱ)问)(19)解:(Ⅰ)依题意,1ξ的所有取值为68.1,92.1,1.2,4.2,…………………1分 因为()30.05.06.068.11=⨯==ξP ,()30.05.06.092.11=⨯==ξP , ()20.05.04.01.21=⨯==ξP ,()20.05.04.04.21=⨯==ξP .………………………3分所以1ξ的分布列为依题意,2ξ的所有取值为68.1,8.1,24.2,4.2,………………………………5分 因为()42.06.07.068.12=⨯==ξP ,()18.06.03.08.12=⨯==ξP , ()28.04.07.024.22=⨯==ξP ,()12.04.03.04.22=⨯==ξP ,……………………………7分所以2ξ的分布列为(Ⅱ)令i Q 表示方案i 所带来的利润,则所以1150.30+200.50+250.20=19.5EQ =⨯⨯⨯,……………8分……………………10分………………………9分……………4分2150.42+200.46+250.12=18.5EQ =⨯⨯⨯. 因为12EQ EQ >,所以实施方案1,第二个月的利润更大.………………………………………………12分(20)解:(Ⅰ)双曲线2215x y -=的焦点坐标为(),离心率为5.………1分 因为双曲线2215x y -=的焦点是椭圆C :22221x y a b+=()0a b >>的顶点,且椭圆与双曲线的离心率互为倒数,所以a ==1b =. 故椭圆C 的方程为1622=+y x .………………………………………………………3分 (Ⅱ)因为2334>=MN ,所以直线MN 的斜率存在.………………………………4分 因为直线MN 在y 轴上的截距为m ,所以可设直线MN 的方程为m kx y +=.代入椭圆方程1622=+y x 得0)1(612)61(222=-+++m kmx x k .………………5分 因为()0)61(24)1)(61(241222222>-+=-+-=∆m k m k km ,所以2261k m +<.………………………………………………………………………6分 设),(11y x M ,),(22y x N ,根据根与系数的关系得1221216kmx x k -+=+,()21226116m x x k -=+.……………………7分则()212212212411x x x x k x x k MN -++=-+==因为334=MN3.………………8分 整理得()22421973918k k k m +++-=.……………………………………………………………………9分令112≥=+t k ,则12-=t k .所以2218755015075230575189993t t m t t t -+-⎡⎤-⨯⎛⎫==-+≤= ⎪⎢⎥⎝⎭⎣⎦.…………10分等号成立的条件是35=t ,此时322=k ,253m =满足2261k m +<,符合题意.…………11分故m 的最大值为315.…………………………………………………………………12分(21)解:(Ⅰ)函数f x 的定义域为),(),(∞+110 .因为ln xf xax b x,所以a xx x f --=2ln 1ln )('.……………………………1分 所以函数f x 在点e,e f 处的切线方程为e e e y a b a x ,即e y ax b .…………………2分已知函数f x 在点e,e f 处的切线方程为2e y ax,比较求得e b.所以实数b 的值为e .……………………………………………………………………3分(Ⅱ)解法1:由e x f +≤41)(,即e e ax x x +≤+-41ln .……………………………4分 所以问题转化为11ln 4a x x≥-在],[2e e 上有解.……………………………………5分 令()11ln 4h x x x=-],[2e e x ∈, 则()h x '22114ln x x x =-222ln 44ln x xx x-=(22ln ln 4ln x x x x +-=. (7)分令()ln p x x =-所以当],[2e e x ∈时,有()10p x x '==<.……………………………8分所以函数()p x 在区间],[2e e 上单调递减.………………………………………9分所以()()e ln e 0p x p <=-<. ……………………………………………10分 所以()0h x '<,即()h x 在区间],[2e e 上单调递减. ……………………………11分所以()()22221111eln e4e 24e h x h ≥=-=-. 所以实数a 的取值围为⎪⎭⎫⎢⎣⎡+∞-,41212e .………………………………………12分 解法2:命题“存在],[2e e x ∈,满足e xf +≤41)(”等价于“当],[2e e x ∈时,有[]e x f +≤41)(min ”.…………………………4分由(Ⅰ)知,a x a x x x f -+⎪⎭⎫⎝⎛--=--=4121ln 1ln 1ln )('22. (1)当41≥a 时,0)('≤x f ,即函数f x 在区间],[2e e 上为减函数,…………5分 所以=min )]([xf 222e ee e 2f a .由min )]([x f ≤1e 4,得41222≤+-e ae e e +,解得24121ea -≥.所以24121e a -≥.…………………………………………………………………6分 (2)当14a时,注意到函数a x x f -+⎪⎭⎫ ⎝⎛--=4121ln 1)('2在区间],[2e e 上的值域为⎥⎦⎤⎢⎣⎡--a a 41,. ……………………………7分 ①0≤a ,)0('≥x f 在区间],[2e e 上恒成立,即函数f x 在区间],[2e e 上为增函数. 所以=min )]([xf e e e e =2e e f a a . 由于min )]([x f ≤1e 4,所以e ae e +≤-412,解得1104ea ≥->,这与0a ≤矛盾. ………8分②若104a,由函数)('x f 的单调性(单调递增)和值域知,存在唯一的()20e,e x ∈,使0)('=x f ,且满足当),(0x e x ∈时,0)('0<x f ,即f x 为减函数;当),(0e x x ∈时,0)('0>x f ,即f x 为增函数.所以=min )]([x f 0f x 000e ln x ax x .…………………………………………9分由≤min )]([x f 1e 4,得00e ln x ax x e ≤1e 4,即0001ln 4x ax x ≤. 因为0)('=x f ,即020ln 10ln x ax ,所以020ln 1ln x ax .将020ln 1ln x ax 代入001ln 4x ax x 41≤,得41ln 020≤x x ,其中()20e,e x ∈.………………10分令2ln x h xx,则x x x h 3ln 2ln )('-=, 当],[2e e x ∈时,0)('≤x h ,即h x 在区间],[2e e 上为减函数.所以=≥)()(2e h h 22222e e 1e >44ln e hx ,与0201ln 4x x ≤矛盾, 所以不存在10,4a ⎛⎫∈ ⎪⎝⎭,使≤min )]([x f 1e 4成立.…………………………11分综上可知,实数a 的取值围为⎪⎭⎫⎢⎣⎡+∞-,41212e .………………………………12分 (说明:当104a时,也可转化为200ln 4x x ≥,其中()20e,e x ∈,从而构造函数()2ln x p x x=解答;还可转化为0041ln 1x x a -≥,从而构造函数11ln 4q x xx解答;还有其他解法均参照给分!)(22)(Ⅰ)解:曲线C 的普通方程为141222=+y x .…………………………………1分 将直线02=--y x 代入141222=+y x 中消去y 得,032=-x x .………………2分 解得0=x 或3=x .…………………………………………………………………3分 所以点()2,0-A ,()1,3B ,……………………………………………………………4分所以()()23210322=++-=AB .……………………………………………5分(Ⅱ)解法1:在曲线C 上求一点P , 使△PAB 的面积最大,则点P 到直线l 的距离最大.设过点P 且与直线l 平行的直线方程为b x y +=.……………………………………6分将b x y +=代入141222=+y x 整理得,()0436422=-++b bx x . 令()()22644340b b ∆=-⨯⨯-=,解得4±=b .…………………………………7分将4±=b 代入方程()0436422=-++b bx x ,解得3±=x .易知当点P 的坐标为()1,3-时,△PAB 的面积最大.………………………………8分 且点P ()1,3-到直线l 的距离为231121322=+---=d .……………………………9分△PAB 的最大面积为=⨯⨯=d AB S 219.…………………………………………10分 解法2:在曲线C 上求一点P , 使△PAB 的面积最大,则点P 到直线l 的距离最大.设曲线C 上点()θθsin 2,cos 32P ,其中[)π2,0∈θ,………………………………6分则点P 到直线l 的距离为22112sin 2cos 32+--=θθd 226πcos 4-⎪⎭⎫ ⎝⎛+=θ.……8分 因为[)π2,0∈θ,则6π136π6π<+≤θ, 所以当π6π=+θ,即65π=θ时,23max =d .……………………………………9分此时点P 的坐标为()1,3-,△PAB 的最大面积为=⨯⨯=d AB S 219.………………10分(23)(Ⅰ)证明1:因为1=++c b a ,所以()()()222111+++++c b a ()32222++++++=c b a c b a 5222+++=c b a .所以要证明()()()316111222≥+++++c b a , 即证明31222≥++c b a .…………………………………………………………1分 因为()()ca bc ab c b a c b a ++-++=++22222 ………………………………2分()()22222c b a c b a ++-++≥,……………………………………………………3分所以()()22223c b a c b a ++≥++.……………………………………………4分因为1=++c b a ,所以31222≥++c b a . 所以()()()316111222≥+++++c b a .…………………………………………5分 证明2:因为1=++c b a ,所以()()()222111+++++c b a ()32222++++++=c b a c b a 5222+++=c b a .所以要证明()()()316111222≥+++++c b a , 即证明31222≥++c b a .………………………………………………………………1分 因为21293a a +≥,21293b b +≥,21293c c +≥,…………………………………3分 所以()2221233a b c a b c +++≥++.…………………………………………………4分因为1=++c b a ,所以31222≥++c b a . 所以()()()316111222≥+++++c b a .………………………………………………5分 证明3:因为()()21681193a a ++≥+,()()21681193b b ++≥+,()()21681193c c ++≥+,…………3分所以()()()()()()22216811111133a b c a b c ++++++≥+++++⎡⎤⎣⎦.…………………4分 因为1=++c b a ,所以()()()316111222≥+++++c b a .……………………………………………5分 (Ⅱ)解:设()12-+-=x a x x f ,则“对任意实数x ,不等式+212x a x --≥恒成立”等价于“()min 2f x ≥⎡⎤⎣⎦”.……6分当21<a 时,()⎪⎪⎪⎩⎪⎪⎪⎨⎧>--≤≤-+-<++-=.21,13,21,1,,13x a x x a a x a x a x x f此时()min 11=22f x f a ⎛⎫=-⎡⎤ ⎪⎣⎦⎝⎭, 要使+212x a x --≥恒成立,必须221≥-a ,解得23-≤a .………………7分 当21=a 时,3221≥-x 不可能恒成立.……………………………………………8分当21>a 时,()⎪⎪⎪⎩⎪⎪⎪⎨⎧>--≤≤-+<++-=.,13,21,1,21,13a x a x a x a x x a x x f 此时()min 11=22f x f a ⎛⎫=-⎡⎤ ⎪⎣⎦⎝⎭,要使+212x a x --≥恒成立,必须221≥-a ,解得25≥a .…………………9分 综上可知,实数a 的取值围为⎪⎭⎫⎢⎣⎡+∞⎥⎦⎤ ⎝⎛-∞-,2523, .…………………………10分。

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