湖南名校株洲市二中2013届高三考前演练理数试题及答案5.27
- 格式:doc
- 大小:831.00 KB
- 文档页数:10
株洲市二中2013届高三高考模拟试题二英语本卷共四个部分,时量120分钟,满分150分试卷总页11页PART ONE LISTENING COMPREHENSIONSECTION ADirections: In this section, you’ll hear 6 conversations between 2 speakers. For each conversation, there are several questions and each question is followed by 3 choices. Listen to the conversations carefully and then answer the questions by marking the corresponding letter (A, B or C) on the question booklet.Conversation 1How much did the woman pay?A. $80.B. $100.C. $120.2. What do we know from the conversation?A. The coat will fit the woman’s son.B. The man doesn’t like the coat at all.C. They are talking about only the price of the coat.Conversation 23. What time will Cathy go to the party?A. Before seven.B. About six thirty.C. After seven.4. Why will the woman be late for the party?A. Because she will take a piano lesson.B. Because she will go over her lessons.C. Because she will have her piano repaired.Conversation 35. What is the probable relationship between the two speakers?A. Son and Mother.B. Boss and Secretary.C. Husband and wife.6. What is the first thing the man is going to do?A. Buy some candles from the store.B. Head for home as soon as possible.C. Telephone the electric company.Conversation 47. What do we know about the old bike?A. Jenny has been using it.B. It was Jenny’s birthday gift.C. The woman will buy it for her daughter.8. What will the man do this Sunday?A. Go camping.B. Go shopping.C. Stay at home.9. When will the two speakers meet?A. This weekend.B. Next weekend.C. Next Monday. Conversation 510. When does John get to school?A. At six o’clock.B. At seven o’clock.C. At eight o’clock11. What does Jenny say about the test?A. It will be hard.B. It will be easy.C. It will be unfair.12. What do we know about John?A. He didn’t study last week.B. He never attended the course at all.C. He is afraid of losing the scholarship.Conversation 613. Why was Bill unhappy about the game?A. Because some players played poorly.B. Because the scores were too close.C. Because it lasted too long.14. Who cheered for the Lions?A. Steve.B. Bill.C. Eric.15. What did Bill enjoy last night?A. Supporting his team.B. Eating some food.C. His friends’ companySECTION BDirections: In this section, you'll hear a mini-talk. Listen carefully and then fill in the numbered blanks with the information you've got. Fill in each blank with NO MORE THAN 3 WORDS.You 'll hear the mini-talk TWICE.Interesting facts about basketballI. The first game of basketball▲Played on 20th January, 1892▲Scored one point▲16 players in each teamII. Women’s basketball▲Started in 1892▲Changed some of the17 to suit womenIII. Introduction of the new ball▲Early on: a soccer ball▲ 18 : the modern basketball.IV. The color of the balls▲Originally: 19▲From the 1950s: orangeV. The tallest basketball players▲Paul Sturgess: 20▲Gheorghe Muresan and Manute Bol: 2.31 metersPART TWO LANGUAGE KNOWLEDGESECTION ADirections: Beneath each of the following sentences there are 4 choices marked A, B, C and D. Choose the one answer that best completes the sentence.21. When James Harden was a kid, his family lived in Compton in Southern California, ________ was well known for its charming scenery.A. thatB. whichC. whenD. where22. Still, students in the U.S have an important exam ______about, which is the US college entrancetest-SAT.A. to worryB. worryingC. worriedD. being worried23. “2012 ______ as a year of extreme weather events around the world.” Said Sullivan from the NOAA at the annual meeting.A. would be rememberedB. was rememberedC. will be rememberedD. had been remembered24. Sometimes the male elephant, which has learned to copy human speech, speaks when ______ to, other times it does freely.A. to tellB. tellC. tellingD. told25. Next to the General manager’s office ______ th e Sales and Marketing Department.A. areB. isC. haveD. has26. The Washington Post reports some teenagers are teased on the Internet and ______ some take more risks on the Internet than they do in person.A. whichB. whereC. thatD. what27. Nobody will know the real reason for its recent strange behaviors, _______ the shark itself speaks up.A. unlessB. ifC. sinceD. though28. Now the Great Wall is in poor condition, so the Chinese authorities ________ on a monitoring and warning system along the wall to preserve it in the future.A. will workB. have workedC. are workingD. work29. The building has been designed to imitate classical Chinese architecture,______ half a million pounds to buildA. costingB. to costC. costD. being cost30. —Sally, this is a T-shirt I bought for you yesterday.—Thank you. You ______ have; I bought two last week.A. shouldn’tB. mightn’tC. couldn’tD. needn’t31. It is in communities across the mountains and the middle hills ______ we have already installed solar systems to supply power.A. whereB. whichC. whenD. that32. If people ______ of the Hurricane Sandy, the 69 victims in the Caribbean would have survived the disaster.A. had informedB. had been informedC. informedD. were informed33. Do remember to make allowance for the traffic and parking when you set off for a job interview, ______ ?A. shall weB. don’t youC. can youD. will you34. Over the last few years, researchers ______ that recreational activities have a number of benefits, especially in this highly competitive society.A. have foundB. foundC. had foundD. was finding35. Years of school life has taught me the importance of teamwork. ______, I didn’t realize its value until I was chosen monitor.A. In additionB. On the contraryC. In factD. At the same timeSECTION BDirections: For each blank in the following passage there are four words or phrases marked A, B, Cand D. Fill in each blank with word or phrases that best fits the context.It was an autumn morning shortly after I moved into our first house. I was looking out of the window when my father moved around 36 on the front grass land.“What are you doing out there?” I called to him. He looked up, smiling. “I’m making you a 37 .”Knowing my father well, I thought it could be just about anything. As a jobber(个体手艺人), he was always building things out of some little things, so I soon 38 his words.Until one raw day of the following March, I glanced out of the window, little piles of dirty snow still stubbornly littering the grass land. Would winter never end? Suddenly, a dot of pink amazingly came out of a drift in the yard. Was it a dream image? I 39 my coat and headed outside for a closer look.Across the muddy grass and melting snow, I stopped and 40 the grass land. They were crocuses(番红花), distributed throughout the front lawn. Blue, yellow and my favorite pink-little faces were waving in the 41 wind. I smiled, remembering the bulbs (球茎)my father had secretly planted last autumn. He knew how the dark and dull winter always got me down. How blessed I was, not only for the 42 , but for him.The crocuses bloomed each spring for the following years, bringing to me that same thought every time they arrived: Hard times are to be over. 43 and light is coming soon. However, a spring came with only half the usual blooms and none from then on. I felt down again.Many years passed by and I 44 the crocuses very much. And every time I passed the grass land, I would have a glance at it. Then, on a pale spring afternoon this year, while I was turning my 45 into my driveway, suddenly a dot of pink attracted me. Was it a crocus? I couldn’t believe it because they had not blossomed in the past ten years? But there was really one pink crocus, 46 waving in the wind. Tears filled my eyes as I realized its significance. The pink crocus bloomed for only a day, but it built my 47 for a lifetime. As a result, I no longer felt down in the following winter days.36. A. secretly B. carefully C. quickly D. confidently37. A. challenge B. chance C. difference D. surprise38. A. broke B. remembered C. forgot D. understood39. A. threw B. seized C. folded D. removed40. A. glared at B. laughed at C. pointed at D. stared at41. A. bitter B. light C. gentle D. strong42. A. snow B. trees C. flowers D. grass43. A. Watch out B. Hold on C. Give up D. Break in44. A. overlooked B. enjoyed C. observed D. missed45. A. plane B. boat C. car D. train46. A. bravely B. sadly C. shyly D. happily47. A. courage B. faith C. strength D. devotionSECTION CDirections: Complete the following passage by using ONE word that best fits the context.My first day at school has left so deep an impression on me that I’ll never forget it. 48 had I rushed into the classroom when the bell rang. A young beautiful but serious woman teacher came in. “You are not permitted to interrupt me in the course of class unless...”. She was speaking 49 I heard a voice “Lily, Lily” from outside the door. My grandmother was standing there, witha pair of socks in her hand. I didn’t realize that I was bare feet50 then. I shook my head, meaning “Don’t wait here any 51 . Leave quickly.” As I did so, I still fixed my eyes on the teacher,52 wanting her to take notice of me, 53 she did. She went out to get the socks. I was so nervous that my shaking hands couldn't get 54 onto my feet easily.Just then I heard my name called and a voice, “Can you count the numbers from one to one hundred?” the teacher said. I nodded and did very well. Finally she said, “Be seated, please. Study hard.” I Looked up at her and found55 smile on her face. I felt relaxed at last. My first day at school has stayed in my memory as something embarrassing but sweet.PART THREE READING COMPREHENSIONDirections: Read the following three passages. Each passage is followed by several questions or unfinished statements. For each of them there are 4 choices marked A, B, C and D. Choose the one that fits best according to the information given in the passage.AI was a medical student. To gather data for my paper, I started visiting patients at Dr Sardjito Hospital, where I would review the medical records of patients and then interview them.One evening, I was in a ward, desperately “hunting” for the fina l three patients I needed to complete my study. Holding a patient questionnaire, I walked towards a room. A patient called Ms A was lying in bed, clearly still weak. There were no relatives or friends with her. Even the bed beside her was empty. I sat down on a chair next to her bed, and in a low voice I introduced myself and asked if I could gather some additional information from her. She agreed. After I finished, I prepared to leave. Before I could stand up, Ms A said, “ I haven’t seen you here before, doctor. Are you new?” “Not really, Madam. It’s just that I don’t come here every day,” I replied. Ms A started talking about herself. She shared her difficulties and sufferings, talked about her husband, who was killed in a car accident, and that she struggled to earn money. All I did was nod my head as a way of showing my sympathy.Without realizing it, I had begun holding Ms A’s hand. Finally, Ms A stopped talking. “I’m very sorry for keeping you here to listen to my problem, but I feel relieved now. I had no one to pour out my problems to.” Tears fell from the corner of her eyes. Finally, I knew what to say. “It’s OK, Madam. It’s part of my duty.” I stood up and waved goodbye. A few days later, when I returned to the ward, I discovered Ms A had left the hospital as her condition had improved.Ms A taught me the most important lessons a doctor can learn. Sometimes patients do not need expensive medicine. They just need someone with the patience and willingness to lend an ear and spare a little of their time.56. Why did the author interview the patients at Dr Sardjito Hospital?A. Because it was the duty as a medical student.B. Because she needed medical information for her paper.C. Because she was going to get a good position there soon.D. Because she wanted to learn about the suffering of patients.57. From Paragraph 2 we can infer that Ms A was feeling________.A. relaxedB. annoyedC. nervousD. lonely58. What do we know about Ms A from the passage?A. She had lost her husband and kidsB. She got hurt in a traffic accidentC. she was living in a tough conditionD. she didn’t get on well with others59. Ms A tended to think that _________.A. The author was kind and patient enough to share her sufferingsB. Other doctors treated her in a cold wayC. She shouldn’t talk about her difficulties to doctorsD. Doctors ought to learn how to cure her psychological problems60. What conclusion did the author draw after interviewing Ms A?A. A doctor must learn how to treat each patient equally.B. Her psychological treatment made Ms A recover quickly.C. Listening is sometimes the best thing a doctor can do for a patient.D. It is the doctors’ duty to receive whatever patients say.BIt must be something that many American companies hold a baby contest. Of course, babies are wonderful, and many parents would be the first to agree. Companies really bring in much money. Walgreens Baby contestIf you play the new Baby Milestones Challenge Contest by BabyCenter & Walgreens, you could win $1,000 in Walgreens & Gift Cards and Certificates. You can play the instant winner if you get a $ 25 Walgreen’s gift card, but you also have to write down your email address and receive all their sales and other information for the contest.Kids and BabiesKids and Babies are accepting entries for May 2013 Free Photo Contest. Baby Photo Galley with theme albums and age group albums is moved to the new website Cute Baby Gallery. Check for their Baby Photo Contest blog’s lates t update. The Grand prize is $ 25,000. The catch: Winners are decided by the visitors coming to the site and voting for their favorite babies, so you have to advertise their site for them. has a website only for their members, but if you are into baby photos, it is well worth surfing. You could receive offers on free samples, money-saving coupons (优惠券), and chances to win the latest contests.AvonAvon is another company that has a baby photo contest this spring. Avon is advertising their newest collection. It is Avon’s only collection for the photos of babies. Babies’ age: newborn to 2 years. Just go to and upload your recent baby’s photos. The first place baby will be featured in a Tiny Tillia Storybooks and win a $ 5,000 U.S. Savings Bond. Ten beautiful girls will win $ 300 worth of Tiny Tillia products.The tip is to run a search engine for all the latest contests going on and start entering them today. You could be lucky and win enough to put your baby through college! Have fun!61. In the author's opinion, companies’ action of holding a baby contest .A. is not reasonable at allB. is funny and interestingC. attracts parents' attentionD. can cost a company much money62. What is the basic condition for you to play the instant winner in Walgreens & ?A. Getting a gift cardB. Getting a certificateC. Winning 1,000 dollarsD. Receiving information for the contest63. If you want your baby to win the 2013 Free Photo Contest, you will _______.A. have to spend $ 25,000B. take your baby to the gallery in MayC. upload more photos of your babyD. have to help to advertise their site64. What can we learn from this passage?A. Free Photo Contest will be held in March, 2013.B. Avon is a website that will hold a baby photo contest.C. Parents. com accepts the photos of all kinds of people' babies.D. Parents can upload their one-year-old baby’s photos to TinyTillia. com.65. In the last paragraph, the author advises parents to _________ .A. try their best to take good care of their babyB. enter the contests as soon as possibleC. encourage their kids to go to college when they grow upD. find more tips for winning the contestsCResearchers at Washington University School of Medicine in ST. Louis have identified a gene that is required for proper development of the mouse ear, providing clues to deafness.In humans, this gene is known as FGF20. “When we inactivated(阻止活动) FGF20, we saw they were alive and healthy,” says senior author David M. Ornitz, Professor of Developmental Biology. “But then we figured out that they had absolutely no ability to hear.”The results show that disabling the gene causes a loss of outer hair cell, a special type of sensory cell in the ear responsible for amplifying(扩大) sound. While about two-thirds of the outer hair cells were missing in mice without FGF20, the number of inner hair cells, the cells responsible for transmitting the amplified signals to the brain, appeared normal.“This is the first evidence that inner and outer hair cells develop independently of one another,” says first author Sung-Ho, PhD, research associate. “This is important because most age-related deafness and heari ng loss caused by noise are due to the loss of outer hair cells.”As such, Ornitz and Huh believe that FGF20 signaling will be a required step toward the goal of regenerating outer hair cells in mammals, incapable of hearing restoration.The FGF20 gene stands for one member of a family of proteins known as fibroblast (纤维组织母细胞) growth factors. In general, members of this family are known to play important and broad roles in embryonic(胚胎的) development, tissue maintenance and wound healing.Ornitz and his colleagues found that FGF20 signaling must occur on or before day 14 of the embryo’s development to produce a normal inner ear. Even if FGF20 signaling occurred on day 15 or later, the inner ear still did not develop properly.“In mice, the cells that can bec ome outer hair cells must be exposed to the FGF20 protein at an early stage,” Ornitz says. “After embryonic day 14, it doesn’t matter if they see the protein. It’s too later for them to become outer hair cells.”66. After FGF20 was inactivated in mice, they __________.A. were not able to walk any moreB. didn’t appear abnormal immediatelyC. died without any symptoms soonD. saw an increase of outer hair cells67. According to the study, inner hair cells __________.A. are not affected by the absence of FGF20B. are responsible for regenerating soundC. will be missing if there isn’t FGF20D. have only been found in mice so far.68. The underlined word “regenerating” in Para. 5 can be replaced by“________”A. reducingB. fighting B. preventing D. reproducing69. What can we learn from the passage?A. Mammals are capable of restoring hearing themselves.B. Age-related deafness may be cured with FGF20 signaling.C. Most deafness among people is caused by the loss of inner hair cells.D. To generate outer hair cells, cells must meet the FGF20 protein on day 14.70. What is the passage mainly about?A. Why people become deaf.B. How to cure deafness.C. A new discovery about the gene PGF20.D. How the ear works.PART FOUR WRITINGSECTION ADirections: Read the following passage. Complete the diagram/Fill in the numbered blanks by using the information for the passage. Write NO MORE THAN 3 WORDS for each answer.We all know eating out can be a lot of fun. There’s th e experience of having someone wait on your every need, the social aspect of being in a restaurant with friends and, of course, the great benefit of the lack of in-home cleanup.We all also know eating out can be expensive, and I’m pretty sure college isn’t the most financially successful time in a normal person’s life. That’s why eating at home for a majority of meals really is the only option for many college students.Eating at home doesn’t have to be dull, boring, or difficult. It can and should be an e nergetic, creative experience that transforms the way you look at food. When you cook for yourself, you know exactly how your pasta(意大利面)is going to turn out. You know where the greens in your salad come from. You know the olive oil you’re using really comes from olives that are pressed for the first time. Use eating at home as an opportunity to learn and develop your kitchen skills. I promise you they will remain useful and rewarding for the rest of your life.Another important concept is to keep in mind that when it comes to shopping for food—less quantity, more quality. Buy base ingredients that are fresh, as local as possible and beautiful, and anything you cook will improve greatly. I promise you will be just as satisfied by eating a little bit less of something with a lot more quality.I am not saying eating out is a bad thing. But I insist there are many more places that are not worth your cash. Put a little more effort into cooking for yourself at home and you will gain experience and appreciation for the world of food.Title : Eating out or at home?I. Eating out: 71 but expensive★having someone wait 72★being in a restaurant 73★Freeing people from in-home cleanup.★Meeting financial problems because of 74II. Eating at home: to be creative and rewarding★Providing an experience to change your view on how you 75 — the way of the pasta turning out, the greens in salad 76 and the truth of olives being pressed for olive oil★77 skills in the kitchen★Being satisfied by eating a little less quantity with 78III. 79★80 and you will gain experience and appreciation for the food worldSECTION BDirections: Read the following passage. Answer the questions according to the information given in the passage and the required words limit. Write your answers on your answer sheet.I still remember the days when I was a youthful student in an engineering school. I lived a casual life, without caring about the future. I smoked, drank with friends and made girl friends. Little did I realize that casualness would certainly lead to loss.Two years had passed and I was staring down a report card that highlighted FALL in more than half the subjects. I didn’t care, at least not until my dad found about it. You see, I studied In India and unlike the United States where the students are expected to finance their own education, my dad financed me.Then came the day when my dad found out my habit of smoking. He lost his temper but he just told me, “Son, your allowance is cut in half from this moment on”. It hit me like a roundhouse kick.(回旋踢) from Bruce Lee. I was shocked out of my bones. I couldn’t comprehend how to pay off the debts that I had accumulated in college. I owed everybody money: the grocery store, the bars, the restaurants, my friends, etc. I was living a life filled with credit.When I went back to college, I knew that if I don’t change the way I live my life I won’t be able to pay everybody off. So I decided to make some changes. I quit smoking, cut off from my friends who led me down the wrong the road, starting hanging out in libraries and reading my engineering books.One year later, I went from a miserable failure to a magna cum laude(优等成绩). Life was never the same again. This incident made me know that anything is possible if you take action and do something about it, however small or large. Even today it still motivates me when I feel that I’m about to lose or give up. It reminds me that I can do it.81. What kind of life did the author live in the engineering school? (No more than 12 words)82. When did the author begin to care about the serious situation? (No more than 14 words)83. How did his father deal with his son’s problem? (No more than 8 words)84. What did the author learn from this incident? (No more than 12 words)SECTION CDirections: Write an English composition according to the instructions given below in Chinese.请你以“My recipe (秘方) for success”为题,写一篇120词左右的短文。
2013年湖南省高考数学试卷(理科)一、选择题:本大题共8小题,每小题5分,共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.(5分)复数z=i•(1+i)(i为虚数单位)在复平面上对应的点位于()A.第一象限B.第二象限C.第三象限D.第四象限2.(5分)某学校有男、女学生各500名,为了解男、女学生在学习兴趣与业余爱好方面是否存在显著差异,拟从全体学生中抽取100名学生进行调查,则宜采用的抽样方法是()A.抽签法B.随机数法C.系统抽样法D.分层抽样法3.(5分)在锐角△ABC中,角A,B所对的边长分别为a,b.若2asinB=b,则角A等于()A.B.C.D.4.(5分)若变量x,y满足约束条件,则x+2y的最大值是()A.B.0 C.D.5.(5分)函数f(x)=2lnx的图象与函数g(x)=x2﹣4x+5的图象的交点个数为()A.3 B.2 C.1 D.06.(5分)已知,是单位向量,,若向量满足,则的取值范围为()A.B.C.D.7.(5分)已知棱长为1的正方体的俯视图是一个面积为1的正方形,则该正方体的正视图的面积不可能是()A.1 B.C.D.8.(5分)在等腰直角三角形ABC中,AB=AC=4,点P是边AB边上异于AB的一点,光线从点P出发,经BC,CA反射后又回到点P(如图),若光线QR经过△ABC的重心,则AP等于()A.2 B.1 C.D.二、填空题:本大题共8小题,考生作答7小题,第小题5分,共35分.(一)选做题(请考生在第9,10,11三题中任选两题作答、如果全做,则按前两题记分)(二)必做题(12~16题)9.在平面直角坐标系xOy中,若直线l:,(t为参数)过椭圆C:(θ为参数)的右顶点,则常数a的值为.10.(5分)已知a,b,c∈R,a+2b+3c=6,则a2+4b2+9c2的最小值为.11.(5分)如图,在半径为的⊙O中,弦AB,CD相交于点P,PA=PB=2,PD=1,则圆心O到弦CD的距离为.12.(5分)若x2dx=9,则常数T的值为.13.(5分)执行如图所示的程序框图,如果输入a=1,b=2,则输出的a的值为.14.(5分)设F1,F2是双曲线C:(a>0,b>0)的两个焦点,P是C上一点,若|PF1|+|PF2|=6a,且△PF1F2的最小内角为30°,则C的离心率为.15.(5分)设S n为数列{a n}的前n项和,S n=(﹣1)n a n﹣,n∈N*,则(1)a3=;(2)S1+S2+…+S100=.16.(5分)设函数f(x)=a x+b x﹣c x,其中c>a>0,c>b>0.(1)记集合M={(a,b,c)|a,b,c不能构成一个三角形的三条边长,且a=b},则(a,b,c)∈M所对应的f(x)的零点的取值集合为.(2)若a,b,c是△ABC的三条边长,则下列结论正确的是.(写出所有正确结论的序号)①∀x∈(﹣∞,1),f(x)>0;②∃x∈R,使a x,b x,c x不能构成一个三角形的三条边长;③若△ABC为钝角三角形,则∃x∈(1,2),使f(x)=0.三、解答题:本大题共6小题,共75分.解答应写出文字说明、证明过程或演算步骤.17.(12分)已知函数f(x)=sin(x﹣)+cos(x﹣),g(x)=2sin2.(Ⅰ)若α是第一象限角,且f(α)=,求g(α)的值;(Ⅱ)求使f(x)≥g(x)成立的x的取值集合.18.(12分)某人在如图所示的直角边长为4米的三角形地块的每个格点(指纵、横直线的交叉点以及三角形顶点)处都种了一株相同品种的作物.根据历年的种植经验,一株该种作物的年收获Y(单位:kg)与它的“相近”作物株数X之间的关系如下表所示:X1234Y51484542这里,两株作物“相近”是指它们之间的直线距离不超过1米.(I)从三角形地块的内部和边界上分别随机选取一株作物,求它们恰好“相近”的概率;(II)在所种作物中随机选取一株,求它的年收获量的分布列与数学期望.19.(12分)如图,在直棱柱ABCD﹣A1B1C1D1中,AD∥BC,∠BAD=90°,AC⊥BD,BC=1,AD=AA1=3.(Ⅰ)证明:AC⊥B1D;(Ⅱ)求直线B1C1与平面ACD1所成的角的正弦值.20.(13分)在平面直角坐标系xOy中,将从点M出发沿纵、横方向到达点N 的任一路径称为M到N的一条“L路径”.如图所示的路径MM1M2M3N与路径MN1N都是M到N的“L路径”.某地有三个新建居民区,分别位于平面xOy内三点A(3,20),B(﹣10,0),C(14,0)处.现计划在x轴上方区域(包含x 轴)内的某一点P处修建一个文化中心.(I)写出点P到居民区A的“L路径”长度最小值的表达式(不要求证明);(II)若以原点O为圆心,半径为1的圆的内部是保护区,“L路径”不能进入保护区,请确定点P的位置,使其到三个居民区的“L路径”长度之和最小.21.(13分)过抛物线E:x2=2py(p>0)的焦点F作斜率率分别为k1,k2的两条不同直线l1,l2,且k1+k2=2.l1与E交于点A,B,l2与E交于C,D,以AB,CD为直径的圆M,圆N(M,N为圆心)的公共弦所在直线记为l.(Ⅰ)若k1>0,k2>0,证明:;(Ⅱ)若点M到直线l的距离的最小值为,求抛物线E的方程.22.(13分)已知a>0,函数.(Ⅰ)记f(x)在区间[0,4]上的最大值为g(a),求g(a)的表达式;(Ⅱ)是否存在a使函数y=f(x)在区间(0,4)内的图象上存在两点,在该两点处的切线互相垂直?若存在,求出a的取值范围;若不存在,请说明理由.2013年湖南省高考数学试卷(理科)参考答案与试题解析一、选择题:本大题共8小题,每小题5分,共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.(5分)(2013•湖南)复数z=i•(1+i)(i为虚数单位)在复平面上对应的点位于()A.第一象限B.第二象限C.第三象限D.第四象限【分析】化简复数z,根据复数与复平面内点的对应关系可得答案.【解答】解:z=i•(1+i)=﹣1+i,故复数z对应的点为(﹣1,1),在复平面的第二象限,故选B.2.(5分)(2013•湖南)某学校有男、女学生各500名,为了解男、女学生在学习兴趣与业余爱好方面是否存在显著差异,拟从全体学生中抽取100名学生进行调查,则宜采用的抽样方法是()A.抽签法B.随机数法C.系统抽样法D.分层抽样法【分析】若总体由差异明显的几部分组成时,经常采用分层抽样的方法进行抽样.【解答】解:总体由男生和女生组成,比例为500:500=1:1,所抽取的比例也是1:1.故拟从全体学生中抽取100名学生进行调查,则宜采用的抽样方法是分层抽样法.故选:D.3.(5分)(2013•湖南)在锐角△ABC中,角A,B所对的边长分别为a,b.若2asinB=b,则角A等于()A.B.C.D.【分析】利用正弦定理可求得sinA,结合题意可求得角A.【解答】解:∵在△ABC中,2asinB=b,∴由正弦定理==2R得:2sinAsinB=sinB,∴sinA=,又△ABC为锐角三角形,∴A=.故选D.4.(5分)(2013•湖南)若变量x,y满足约束条件,则x+2y的最大值是()A.B.0 C.D.【分析】作出题中不等式组表示的平面区域,得如图的△ABC及其内部,再将目标函数z=x+2y对应的直线进行平移,可得当x=,y=时,x+2y取得最大值为.【解答】解:作出不等式组表示的平面区域,得到如图的△ABC及其内部,其中A(﹣,﹣1),B(,),C(2,﹣1)设z=F(x,y)=x+2y,将直线l:z=x+2y进行平移,当l经过点B时,目标函数z达到最大值∴z=F(,)=最大值故选:C5.(5分)(2013•湖南)函数f(x)=2lnx的图象与函数g(x)=x2﹣4x+5的图象的交点个数为()A.3 B.2 C.1 D.0【分析】本题考查的知识点是指数函数的图象,要求函数f(x)=2lnx的图象与函数g(x)=x2﹣4x+5的图象的交点个数,我们画出函数的图象后,利用数形结合思想,易得到答案.【解答】解:在同一坐标系下,画出函数f(x)=2lnx的图象与函数g(x)=x2﹣4x+5的图象如图:由图可知,两个函数图象共有2个交点故选B.6.(5分)(2013•湖南)已知,是单位向量,,若向量满足,则的取值范围为()A.B.C.D.【分析】令,,,作出图象,根据图象可求出的最大值、最小值.【解答】解:令,,,如图所示:则,又,所以点C在以点D为圆心、半径为1的圆上,易知点C与O、D共线时达到最值,最大值为+1,最小值为﹣1,所以的取值范围为[﹣1,+1].故选A.7.(5分)(2013•湖南)已知棱长为1的正方体的俯视图是一个面积为1的正方形,则该正方体的正视图的面积不可能是()A.1 B.C.D.【分析】求出满足条件的该正方体的正视图的面积的范围为即可得出.【解答】解:水平放置的正方体,当正视图为正方形时,其面积最小为1;当正视图为对角面时,其面积最大为.因此满足棱长为1的正方体的俯视图是一个面积为1的正方形,则该正方体的正视图的面积的范围为.因此可知:A,B,D皆有可能,而<1,故C不可能.故选C.8.(5分)(2013•湖南)在等腰直角三角形ABC中,AB=AC=4,点P是边AB边上异于AB的一点,光线从点P出发,经BC,CA反射后又回到点P(如图),若光线QR经过△ABC的重心,则AP等于()A.2 B.1 C.D.【分析】建立坐标系,设点P的坐标,可得P关于直线BC的对称点P1的坐标,和P关于y轴的对称点P2的坐标,由P1,Q,R,P2四点共线可得直线的方程,由于过△ABC的重心,代入可得关于a的方程,解之可得P的坐标,进而可得AP的值.【解答】解:建立如图所示的坐标系:可得B(4,0),C(0,4),故直线BC的方程为x+y=4,△ABC的重心为(,),设P(a,0),其中0<a<4,则点P关于直线BC的对称点P1(x,y),满足,解得,即P1(4,4﹣a),易得P关于y轴的对称点P2(﹣a,0),由光的反射原理可知P1,Q,R,P2四点共线,直线QR的斜率为k==,故直线QR的方程为y=(x+a),由于直线QR过△ABC的重心(,),代入化简可得3a2﹣4a=0,解得a=,或a=0(舍去),故P(,0),故AP=故选D二、填空题:本大题共8小题,考生作答7小题,第小题5分,共35分.(一)选做题(请考生在第9,10,11三题中任选两题作答、如果全做,则按前两题记分)(二)必做题(12~16题)9.(2013•湖南)在平面直角坐标系xOy中,若直线l:,(t为参数)过椭圆C:(θ为参数)的右顶点,则常数a的值为3.【分析】直接划参数方程为普通方程得到直线和椭圆的普通方程,求出椭圆的右顶点,代入直线方程即可求得a的值.【解答】解:由直线l:,得y=x﹣a,再由椭圆C:,得,①2+②2得,.所以椭圆C:的右顶点为(3,0).因为直线l过椭圆的右顶点,所以0=3﹣a,所以a=3.故答案为3.10.(5分)(2013•湖南)已知a,b,c∈R,a+2b+3c=6,则a2+4b2+9c2的最小值为12.【分析】根据柯西不等式,得(a+2b+3c)2=(1×a+1×2b+1×3c)2≤(12+12+12)(a2+4b2+9c2)=3(a2+4b2+9c2),化简得a2+4b2+9c2≥12,由此可得当且仅当a=2,b=1,c=时,a2+4b2+9c2的最小值为12.【解答】解:∵a+2b+3c=6,∴根据柯西不等式,得(a+2b+3c)2=(1×a+1×2b+1×3c)2≤(12+12+12)[a2+(2b)2+(3c)2]化简得62≤3(a2+4b2+9c2),即36≤3(a2+4b2+9c2)∴a2+4b2+9c2≥12,当且仅当a:2b:3c=1:1:1时,即a=2,b=1,c=时等号成立由此可得:当且仅当a=2,b=1,c=时,a2+4b2+9c2的最小值为12故答案为:1211.(5分)(2013•湖南)如图,在半径为的⊙O中,弦AB,CD相交于点P,PA=PB=2,PD=1,则圆心O到弦CD的距离为.【分析】首先利用相交弦定理求出CD的长,再利用勾股定理求出圆心O到弦CD 的距离,注意计算的正确率.【解答】解:由相交弦定理得,AP×PB=CP×PD,∴2×2=CP•1,解得:CP=4,又PD=1,∴CD=5,又⊙O的半径为,则圆心O到弦CD的距离为d===.故答案为:.12.(5分)(2013•湖南)若x2dx=9,则常数T的值为3.【分析】利用微积分基本定理即可求得.【解答】解:==9,解得T=3,故答案为:3.13.(5分)(2013•湖南)执行如图所示的程序框图,如果输入a=1,b=2,则输出的a的值为9.【分析】分析程序中各变量、各语句的作用,再根据流程图所示的顺序,可知:该程序的作用是利用循环累加a值,并判断满足a>8时输出a的值.【解答】解:程序在运行过程中各变量的聚会如下表示:是否继续循环 a b循环前/1 2第一圈是 3 2第二圈是 5 2第三圈是7 2第四圈是9 2第五圈否故最终输出的a值为9.故答案为:9.14.(5分)(2013•湖南)设F1,F2是双曲线C:(a>0,b>0)的两个焦点,P是C上一点,若|PF1|+|PF2|=6a,且△PF1F2的最小内角为30°,则C 的离心率为.【分析】利用双曲线的定义求出|PF1|,|F1F2|,|PF2|,然后利用最小内角为30°结合余弦定理,求出双曲线的离心率.【解答】解:因为F1、F2是双曲线的两个焦点,P是双曲线上一点,且满足|PF1|+|PF2|=6a,不妨设P是双曲线右支上的一点,由双曲线的定义可知|PF1|﹣|PF2|=2a所以|F1F2|=2c,|PF1|=4a,|PF2|=2a,∵△PF1F2的最小内角∠PF1F2=30°,由余弦定理,∴|PF2|2=|F1F2|2+|PF1|2﹣2|F1F2||PF1|cos∠PF1F2,即4a2=4c2+16a2﹣2×2c×4a×,∴c2﹣2ca+3a2=0,∴c=a所以e==.故答案为:.15.(5分)(2013•湖南)设S n为数列{a n}的前n项和,S n=(﹣1)n a n﹣,n ∈N*,则(1)a3=﹣;(2)S1+S2+…+S100=.【分析】(1)把给出的数列递推式先分n=1和n≥2讨论,由此求出首项和n≥2时的关系式.对此关系式再分n为偶数和奇数分别得到当n为偶数和奇数时的通项公式,则a3可求;(2)把(1)中求出的数列的通项公式代入,n∈N*,则利用数列的分组求和和等比数列的前n项和公式可求得结果.【解答】解:由,n∈N*,当n=1时,有,得.当n≥2时,.即.若n为偶数,则.所以(n为正奇数);若n为奇数,则=.所以(n为正偶数).所以(1).故答案为﹣;(2)因为(n为正奇数),所以﹣,又(n为正偶数),所以.则.,.则.….所以,S1+S2+S3+S4+…+S99+S100====.故答案为.16.(5分)(2013•湖南)设函数f(x)=a x+b x﹣c x,其中c>a>0,c>b>0.(1)记集合M={(a,b,c)|a,b,c不能构成一个三角形的三条边长,且a=b},则(a,b,c)∈M所对应的f(x)的零点的取值集合为{x|0<x≤1} .(2)若a,b,c是△ABC的三条边长,则下列结论正确的是①②③.(写出所有正确结论的序号)①∀x∈(﹣∞,1),f(x)>0;②∃x∈R,使a x,b x,c x不能构成一个三角形的三条边长;③若△ABC为钝角三角形,则∃x∈(1,2),使f(x)=0.【分析】(1)由集合M中的元素满足的条件,得到c≥a+b=2a,求得的范围,解出函数f(x)=a x+b x﹣c x的零点,利用不等式可得零点x的取值集合;(2)对于①,把函数式f(x)=a x+b x﹣c x变形为,利用指数函数的单调性即可证得结论成立;对于②,利用取特值法说明命题是正确的;对于③,由△ABC为钝角三角形说明f(2)<0,又f(1)>0,由零点的存在性定理可得命题③正确.【解答】解:(1)因为c>a,由a,b,c不能构成一个三角形的三条边长得c≥a+b=2a,所以,则.令f(x)=a x+b x﹣c x=.得,所以.又∵>1,则ln>0,所以x=>0,所以0<x≤1.故答案为{x|0<x≤1};(2)①因为,又,所以对∀x∈(﹣∞,1),.所以命题①正确;②令x=﹣1,a=2,b=4,c=5.则a x=,b x=,c x=.不能构成一个三角形的三条边长.所以命题②正确;③若三角形为钝角三角形,则a2+b2﹣c2<0.f(1)=a+b﹣c>0,f(2)=a2+b2﹣c2<0.所以∃x∈(1,2),使f(x)=0.所以命题③正确.故答案为①②③.三、解答题:本大题共6小题,共75分.解答应写出文字说明、证明过程或演算步骤.17.(12分)(2013•湖南)已知函数f(x)=sin(x﹣)+cos(x﹣),g(x)=2sin2.(Ⅰ)若α是第一象限角,且f(α)=,求g(α)的值;(Ⅱ)求使f(x)≥g(x)成立的x的取值集合.【分析】(1)利用两角和差的三角公式化简函数f(x)的解析式,可得f(α)的解析式,再根据f(α)=,求得cosα的值,从而求得g(α)=2sin2=1﹣cosα的值.(2)由不等式可得sin(x+)≥,解不等式2kπ+≤x+≤2kπ+,k ∈z,求得x的取值集合.【解答】解:(1)∵f(x)=sinx﹣cosx+cosx+sinx=sinx,所以f(α)=sinα=,所以sinα=.又α∈(0,),所以cosα=,所以g(α)=2sin2=1﹣cosα=.(2)由f(x)≥g(x)得sinx≥1﹣cosx,所以sinx+cosx=sin(x+)≥.解2kπ+≤x+≤2kπ+,k∈z,求得2kπ≤x≤2kπ+,k∈z,所以x的取值范围为〔2kπ,2kπ+〕k∈z.18.(12分)(2013•湖南)某人在如图所示的直角边长为4米的三角形地块的每个格点(指纵、横直线的交叉点以及三角形顶点)处都种了一株相同品种的作物.根据历年的种植经验,一株该种作物的年收获Y(单位:kg)与它的“相近”作物株数X之间的关系如下表所示:X1234Y51484542这里,两株作物“相近”是指它们之间的直线距离不超过1米.(I)从三角形地块的内部和边界上分别随机选取一株作物,求它们恰好“相近”的概率;(II)在所种作物中随机选取一株,求它的年收获量的分布列与数学期望.【分析】(I)确定三角形地块的内部和边界上的作物株数,分别求出基本事件的个数,即可求它们恰好“相近”的概率;(II)确定变量的取值,求出相应的概率,从而可得年收获量的分布列与数学期望.【解答】解:(I)所种作物总株数N=1+2+3+4+5=15,其中三角形地块内部的作物株数为3,边界上的作物株数为12,从三角形地块的内部和边界上分别随机选取一株的不同结果有=36种,选取的两株作物恰好“相近”的不同结果有3+3+2=8,∴从三角形地块的内部和边界上分别随机选取一株作物,求它们恰好“相近”的概率为=;(II)先求从所种作物中随机选取一株作物的年收获量为Y的分布列∵P(Y=51)=P(X=1),P(48)=P(X=2),P(Y=45)=P(X=3),P(Y=42)=P (X=4)∴只需求出P(X=k)(k=1,2,3,4)即可记n k为其“相近”作物恰有k株的作物株数(k=1,2,3,4),则n1=2,n2=4,n3=6,n4=3由P(X=k)=得P(X=1)=,P(X=2)=,P(X=3)==,P(X=4)==∴所求的分布列为Y51484542P数学期望为E(Y)=51×+48×+45×+42×=4619.(12分)(2013•湖南)如图,在直棱柱ABCD﹣A1B1C1D1中,AD∥BC,∠BAD=90°,AC⊥BD,BC=1,AD=AA1=3.(Ⅰ)证明:AC⊥B1D;(Ⅱ)求直线B1C1与平面ACD1所成的角的正弦值.【分析】(I)根据直棱柱性质,得BB1⊥平面ABCD,从而AC⊥BB1,结合BB1∩BD=B,证出AC⊥平面BB1D,从而得到AC⊥B1D;(II)根据题意得AD∥B1C1,可得直线B1C1与平面ACD1所成的角即为直线AD与平面ACD1所成的角.连接A1D,利用线面垂直的性质与判定证出AD1⊥平面A1B1D,从而可得AD1⊥B1D.由AC⊥B1D,可得B1D⊥平面ACD1,从而得到∠ADB1与AD与平面ACD1所成的角互余.在直角梯形ABCD中,根据Rt△ABC∽Rt△DAB,算出AB=,最后在Rt△AB1D中算出B1D=,可得cos∠ADB1=,由此即可得出直线B1C1与平面ACD1所成的角的正弦值.【解答】解:(I)∵BB1⊥平面ABCD,AC⊂平面ABCD,∴AC⊥BB1,又∵AC⊥BD,BB1、BD是平面BB1D内的相交直线∴AC⊥平面BB1D,∵B1D⊂平面BB1D,∴AC⊥B1D;(II)∵AD∥BC,B1C1∥BC,∴AD∥B1C1,由此可得:直线B1C1与平面ACD1所成的角等于直线AD与平面ACD1所成的角(记为θ),连接A1D,∵直棱柱ABCD﹣A1B1C1D1中,∠BAD=∠B1A1D1=90°,∴B1A1⊥平面A1D1DA,结合AD1⊂平面A1D1DA,得B1A1⊥AD1又∵AD=AA1=3,∴四边形A1D1DA是正方形,可得AD1⊥A1D∵B1A1、A1D是平面A1B1D内的相交直线,∴AD1⊥平面A1B1D,可得AD1⊥B1D,由(I)知AC⊥B1D,结合AD1∩AC=A可得B1D⊥平面ACD1,从而得到∠ADB1=90°﹣θ,∵在直角梯形ABCD中,AC⊥BD,∴∠BAC=∠ADB,从而得到Rt△ABC∽Rt△DAB 因此,,可得AB==连接AB1,可得△AB1D是直角三角形,∴B1D2=B1B2+BD2=B1B2+AB2+BD2=21,B1D=在Rt△AB1D中,cos∠ADB1===,即cos(90°﹣θ)=sinθ=,可得直线B1C1与平面ACD1所成的角的正弦值为.20.(13分)(2013•湖南)在平面直角坐标系xOy中,将从点M出发沿纵、横方向到达点N的任一路径称为M到N的一条“L路径”.如图所示的路径MM1M2M3N与路径MN1N都是M到N的“L路径”.某地有三个新建居民区,分别位于平面xOy内三点A(3,20),B(﹣10,0),C(14,0)处.现计划在x 轴上方区域(包含x轴)内的某一点P处修建一个文化中心.(I)写出点P到居民区A的“L路径”长度最小值的表达式(不要求证明);(II)若以原点O为圆心,半径为1的圆的内部是保护区,“L路径”不能进入保护区,请确定点P的位置,使其到三个居民区的“L路径”长度之和最小.【分析】(I)根据“L路径”的定义,可得点P到居民区A的“L路径”长度最小值;(II)由题意知,点P到三个居民区的“L路径”长度之和的最小值为点P到三个居民区的“L路径”长度最小值之和(记为d)的最小值,分类讨论,利用绝对值的几何意义,即可求得点P的坐标.【解答】解:设点P的坐标为(x,y),则(I)点P到居民区A的“L路径”长度最小值为|x﹣3|+|y﹣20|,y∈[0,+∞);(II)由题意知,点P到三个居民区的“L路径”长度之和的最小值为点P到三个居民区的“L路径”长度最小值之和(记为d)的最小值①当y≥1时,d=|x+10|+|x﹣14|+|x﹣3|+2|y|+|y﹣20|∵d1(x)=|x+10|+|x﹣14|+|x﹣3|≥|x+10|+|x﹣14|≥24∴当且仅当x=3时,d1(x)=|x+10|+|x﹣14|+|x﹣3|的最小值为24∵d2(y)=2|y|+|y﹣20|≥21∴当且仅当y=1时,d2(y)=2|y|+|y﹣20|的最小值为21∴点P的坐标为(3,1)时,点P到三个居民区的“L路径”长度之和的最小,且最小值为45;②当0≤y≤1时,由于“L路径”不能进入保护区,∴d=|x+10|+|x﹣14|+|x﹣3|+1+|1﹣y|+|y|+|y﹣20|此时d1(x)=|x+10|+|x﹣14|+|x﹣3|,d2(y)=1+|1﹣y|+|y|+|y﹣20|=22﹣y ≥21由①知d1(x)=|x+10|+|x﹣14|+|x﹣3|≥24,∴d1(x)+d2(y)≥45,当且仅当x=3,y=1时等号成立综上所述,在点P(3,1)处修建文化中心,可使该文化中心到三个居民区的“L路径”长度之和最小.21.(13分)(2013•湖南)过抛物线E:x2=2py(p>0)的焦点F作斜率率分别为k1,k2的两条不同直线l1,l2,且k1+k2=2.l1与E交于点A,B,l2与E交于C,D,以AB,CD为直径的圆M,圆N(M,N为圆心)的公共弦所在直线记为l.(Ⅰ)若k1>0,k2>0,证明:;(Ⅱ)若点M到直线l的距离的最小值为,求抛物线E的方程.【分析】(Ⅰ)由抛物线方程求出抛物线的焦点坐标,写出两条直线的方程,由两条直线方程和抛物线方程联立求出圆M和圆N的圆心M和N的坐标,求出向量和的坐标,求出数量积后转化为关于k1和k2的表达式,利用基本不等式放缩后可证得结论;(Ⅱ)利用抛物线的定义求出圆M和圆N的直径,结合(Ⅰ)中求出的圆M和圆N的圆心的坐标,写出两圆的方程,作差后得到两圆的公共弦所在直线方程,由点到直线的距离公式求出点M到直线l的距离,利用k1+k2=2转化为含有一个未知量的代数式,配方后求出最小值,由最小值等于求出p的值,则抛物线E的方程可求.【解答】解:(I)由题意,抛物线E的焦点为,直线l1的方程为.由,得.设A,B两点的坐标分别为(x1,y1),(x2,y2),则x1,x2是上述方程的两个实数根.从而x1+x2=2pk1,.所以点M的坐标为,.同理可得点N的坐标为,.于是.由题设k1+k2=2,k1>0,k2>0,k1≠k2,所以0<.故.(Ⅱ)由抛物线的定义得,,所以,从而圆M的半径.故圆M的方程为,化简得.同理可得圆N的方程为于是圆M,圆N的公共弦所在的直线l的方程为.又k2﹣k1≠0,k1+k2=2,则l的方程为x+2y=0.因为p>0,所以点M到直线l的距离为=.故当时,d取最小值.由题设,解得p=8.故所求抛物线E的方程为x2=16y.22.(13分)(2013•湖南)已知a>0,函数.(Ⅰ)记f(x)在区间[0,4]上的最大值为g(a),求g(a)的表达式;(Ⅱ)是否存在a使函数y=f(x)在区间(0,4)内的图象上存在两点,在该两点处的切线互相垂直?若存在,求出a的取值范围;若不存在,请说明理由.【分析】(I)利用绝对值的几何意义,分类讨论,结合导数确定函数的单调性,从而可得g(a)的表达式;(II)利用曲线y=f(x)在两点处的切线互相垂直,建立方程,从而可转化为集合的运算,即可求得结论.【解答】解:(I)当0≤x≤a时,;当x>a时,∴当0≤x≤a时,,f(x)在(0,a)上单调递减;当x>a时,,f(x)在(a,+∞)上单调递增.①若a≥4,则f(x)在(0,4)上单调递减,g(a)=f(0)=②若0<a<4,则f(x)在(0,a)上单调递减,在(a,4)上单调递增∴g(a)=max{f(0),f(4)}∵f(0)﹣f(4)==∴当0<a≤1时,g(a)=f(4)=;当1<a<4时,g(a)=f(0)=,综上所述,g(a)=;(II)由(I)知,当a≥4时,f(x)在(0,4)上单调递减,故不满足要求;当0<a<4时,f(x)在(0,a)上单调递减,在(a,4)上单调递增,若存在x1,x2∈(0,4)(x1<x2),使曲线y=f(x)在两点处的切线互相垂直,则x1∈(0,a),x2∈(a,4),且f′(x1)f′(x2)=﹣1∴•=﹣1∴①∵x1∈(0,a),x2∈(a,4),∴x1+2a∈(2a,3a),∈(,1)∴①成立等价于A=(2a,3a)与B=(,1)的交集非空∵,∴当且仅当0<2a<1,即时,A∩B≠∅综上所述,存在a使函数y=f(x)在区间(0,4)内的图象上存在两点,在该两点处的切线互相垂直,且a的取值范围是(0,).。
株洲市二中2013届高三考前演练文科综合能力测试本试卷分为第I卷和第II卷两部分。
第I卷(选择题)1至6页,第II卷(非选择题)7至11页。
满分300分。
考试时量150分钟。
第Ⅰ卷(选择题,共140分)本卷共35小题,每小题4分,共计140分。
每小题列出的四个选项中,只有一项符合题目要求近十年来,我国城市地铁建设开始明显加快,除北京、天津、上海、广州等外,这种地下运行为主的城市铁路与捷运系统,已在南京、沈阳、成都、武汉、西安、重庆、深圳、苏州等10余个城市开通。
据此,并结合所学知识完成1-2题。
1.上述大城市积极兴建地下隧道铁路交通系统的主要目的是A.调整产业结构,扩大就业机会B.节省地面空间,美化地表景观C.减少能源消耗,保护城市环境 D.缓解交通拥堵,节省通勤时间2.针对近些年一些大城市夏季出现的实际问题,地铁在设计与规划时必须充分考虑A.停水断电预案制定 B.防水排水设施C.隧道塌方修复机制 D.防火通风设施表1为2000年和2010年四省市跨省流动人口状况简表(单位:万人)。
分析完成3-4题。
表13.十年间外省流动人口增加数最大和流动人口增长率最小的省级行政区分别是A.广东省,福建省 B.浙江省,天津市C.天津市,福建省 D.广东省,浙江省4.据表中信息可推断A.广东省城镇化速度最快 B.天津市逆城市化突显C.浙江省行政区面积最大 D.福建省老龄化最严重某科研机构收集了1959-2009年我国某山脉南坡与北坡地区多个标准气象站点的逐年月气象资料,利用GIS 技术分析研究了50多年来该地气候变化趋势及气温变化(图1所示为各年一月平均气温变化)。
据此读图回答5-7题。
图2图35.图中显示,近50年来该山脉南坡地区的1月平均气温A.在逐年升高 B.比北坡变化幅度大C.1988年增幅最大 D.约增加了0.7℃左右6.近50年该山地的气候变化会使A.南坡的年降水量增加 B.南、北坡的自然差异加大C.高山林带的上界升高 D.北坡哺乳动物向南迁移7.据提供信息推断,该山脉应是A.南岭 B.秦岭 C.阴山 D.天山“稻鱼鸭”是我国黔东南地区侗族、水族的传统耕作方法,该耕作方法不使用化肥农药,在稻田里既可养鱼又可养鸭。
2013年高考模拟系列试卷(二)数学试题【新课标版】(理科)注意事项:1.本试卷分第Ⅰ卷(阅读题)和第Ⅱ卷(表达题)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.作答时,将答案写在答题卡上。
写在本试卷上无效。
3.考试结束后,将本试卷和答题卡一并交回.第Ⅰ卷(选择题,共60分)一、本题共12小题,每小题5分,共60分,在每小题给出的四个选项中只有一个选项是符合题目要求的 1、设集合{}21,M x x x =-≤∈R ,{}21,02N y y xx ==-+≤≤,则()RM N ⋂等于 ( )A .RB .{}|1x x R x ∈≠且C .{}1D .∅ 2、在复平面内,复数2013i i 1iz =+-表示的点所在的象限是( )A .第一象限B .第二象限C .第三象限D .第四象限3、若sin 601233,log cos 60,log tan 30a b c ===,则( )A .a b c >>B .b c a >>C .c b a >>D .b a c >>4、设数列{}na 是公差不为零的等差数列,它的前n 项和为nS ,且1S 、2S 、4S 成等比数列,则41aa 等于( )A .6B .7C .4D .35、已知点()1,0A -和圆222x y +=上一动点P ,动点M 满足2MA AP =,则点M 的轨迹方程是( )A .()2231x y -+=B .223()12x y -+=C .2231()22x y -+= D .223122x y ⎛⎫+-= ⎪⎝⎭ 6、命题“存在,αβ∈R ,使22sin()sin()sin sin αβαβαβ+-≥-”的否定为( ) A .任意,αβ∈R ,使22sin()sin()sin sin αβαβαβ+-≥- B .任意,αβ∈R ,使22sin()sin()sin sin αβαβαβ+-<- C .存在,αβ∈R ,使22sin()sin()sin sin αβαβαβ+-<- D .存在,αβ∈R ,使22sin()sin()sin sin αβαβαβ+-≤-7、设a b <,函数()()2y x a x b =--的图象可能是( )8、程序框图如下:如果上述程序运行的结果S 的值比2013小,若使输出的S 最大,那么判断框中应填入( ) A .10k ≤ B .10k ≥ C .9k ≤ D .9k ≥9、图为一个空间几何体的三视图,其中俯视图是下边一个等边三角形,其内切圆的半径是1,正视图和侧视图是上边两个图形,数据如图,则此几何体的体积是( )A .1533πB .233πC .33πD .433π10、在9212x x ⎛⎫- ⎪⎝⎭的展开式中,常数项为( )A .5376-B .5376C .84-D .8411、如果点P 在平面区域220140x y x x y -+≤⎧⎪≥-⎨⎪+-≤⎩上,点Q 在曲线(x -1)2+(y-1)2=1上,那么|PQ |的最小值为( ) A .5-1B .355C .3515-D .523-112、已知椭圆C :22221(0)x y a b a b+=>>的左右焦点为12,F F ,过2F 的直线与圆222()()x a y b b -+-=相切于点A,并与椭圆C 交与不同的两点P,Q,如图,若A 为线段PQ 的靠近P 的三等分点,则椭圆的离心率为 ( )A .23B .33C .53D .73第Ⅱ卷(非选择题,共90分)二、填空题:本大题共4小题,每小题4分,共16分,把答案填在题中横线上13、由曲线23y x =-和直线2y x =所围成的面积为 。
株洲市二中2013届高三考前演练理科数学试题(6月)第Ⅰ卷 (共40分)一.选择题(本大题共8小题,每小题5分,共40分.在每小题给出的四个选项中, 只有一项是符合要求的.)1.若集合{|01}A x x =≤<,2{|2}B x x x =<,则A B =( A ) A.{|01}x x << B. {|01}x x ≤< C. {|01}x x <≤ D. {|01}x x ≤≤ 2.若复数z 满足:1(1)z z i +=-,则复数z =( B ) A. iB. i -C.1i -D.1i +3.若一个四面体的四个面均为直角三角形,正视图与俯视图如图所示,均为直角边为1的等腰直角三角形,则该几何体的侧视图的面积为( C )A .14 B.12 D.4.若ABC ∆的三个内角满足sin :sin :sin 5:11:13A B C =,则ABC ∆( C ) A. 一定是锐角三角形 B. 一定是直角三角形 C. 一定是钝角三角形D. 可能是锐角三角形,也可能是钝角三角形5.按右面的程序框图运行后,输出的S 应为( BA ..3 C .46.函数()()220,2cos 02x x f x x x π+-≤⎧⎪=⎨⎛⎫≤≤ ⎪⎪⎝⎭⎩<的图象与x 轴所围成的封闭图形的面积为( D )A. 32B. 52C. 3D. 47.设1F ,2F 分别为双曲线22221(0,0)x y a b a b -=>>的左、右焦点,若在双曲线右支正视图俯视图上存在一点P ,满足212||||PF F F =,且2F 到直线1PF 的距离等于双曲线的实轴长,则该双曲线的离心率为( B )A. 34B. 35C. 45D. 4418.已知函数2,01,()12, 1.2x x x f x x +<⎧⎪=⎨+⎪⎩≤≥若0a b >≥,且()()f a f b =,则()bf a 的取值范围是( A )A. 5[,3)4B. 5[,3)2C. 1[,3)2 D. [1,3)第Ⅱ卷 (共110分)二.填空题(本大题共8个小题,考生作答7个小题,每小题5分,共35分.把答案填在答题卡中对应题号后的横线上.)(一)选做题:请考生在第9、10、11三个小题中任选2题作答,如果全做,则按前2题给分. 9.(选修4—1:几何证明选讲) 以Rt ABC ∆的直角边AB 为直径的圆O 交AC 边于点E ,点D 在BC 上, 且DE 与圆O 相切.若056A ∠=,则BDE ∠= 068 . 10.(选修4—4:坐标系与参数方程)在极坐标系中,已知点)4A π,曲线2sin 4cos ρθθ=的焦点为F , 则||AF = 5 . 11.(选修4—5:不等式选讲)若正数a ,b 满足a +b =1,则13a +2+43b +2的最小值为 97 .(二)必做题:第12——16题12.在△ABC 中,已知AB =2,∠ABC =60°,AD ⊥BC ,D 为垂足,则AD AC ⋅= 3 . 13.采用系统抽样方法从960人中抽取32人做问卷调查,为此将他们随机编号为1,2, …,960,分组后在第一组采用简单随机抽样的方法抽到的号码为9. 抽到的32人中,编号落入区间[]1,450的人做问卷A ,编号落入区间[]451,750的人做问卷B ,其余的人做问卷C . 则抽到的人中,做问卷B 的人数为 10 .EDC B A14.已知函数3()f x x x =+,对任意的[2,2]m ∈-,(2)()0f mx f x -+<恒成立, 则实数x 的取值范围是2(2,)3- . 15.将一颗骰子连续抛掷三次,它落地时向上的点数依次构成等比数列的概率与构成等差数列的概率之比为 49 .16.已知函数2()4sin sin ()cos 242xf x x xπ=⋅++.(1)设0ω>为常数,若()y f x ω=在区间2[,]23ππ-上是增函数,则ω的取值范围是 3(0,]4 ;(2)若|()|2f x m -<成立的充分条件是263x ππ≤≤,则实数m 的取值范围是(1,4).三、解答题(本大题共6小题,共75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)某校设计了一个实验考查方案:考生从6道备选题中一次性随机抽取3道题,按照题目 要求独立完成全部实验操作.规定:至少正确完成其中2道题的便可通过.已知6道备选 题中考生甲有4道题能正确完成,2道题不能完成;考生乙每题正确完成的概率都是23,且每题正确完成与否互不影响.(1)求甲、乙两考生正确完成题数的概率分布列,并计算其数学期望; (2)请分析比较甲、乙两考生的实验操作能力. 解:(1)设甲、乙正确完成实验操作的题数分别为ξ,η, 则ξ取值分别为3,2,1;η取值分别为3,2,1,0.51)1(362214===ξC C C P ,53)2(361224===ξC C C P ,51)3(360234===ξC C C P . ∴考生甲正确完成题数的概率分布列为2513532511=⨯+⨯+⨯=ξE .…………………………3分∵==)0(ηP 271)321(303=-C , 同理:276)1(==ηP ,2712)2(==ηP ,278)3(==ηP .∴考生乙正确完成题数的概率分布列为:227832712227612710=⨯+⨯+⨯+⨯=ηE .………………7分(2)∵5251)32(53)22(51)12(222=⨯-+⨯-+⨯-=ξD ,32278)32(2712)22(276)12(271)02(2222=⨯-+⨯-+⨯-+⨯-=ηD .(或32==npq D η).∴η<ξD D .∵8.05153)2(=+=≥ξP ,74.02782712)2(≈+=≥ηP ,∴)2()2(≥η>≥ξP P .……………10分 从做对题数的数学期望考察,两人水平相当;从做对题数的方差考察,甲较稳定;从至少完成2道题的概率考察,甲获得通过的可能性大. 因此可以判断甲的实验操作能力较强.……………………12分18.(本小题满分12分)在数列{}n a 中,123a =,且对任意的n N *∈都有121n n n a a a +=+. (1)求证:1{1}n a -是等比数列;(2)若对任意的n N *∈都有1n n a pa +<,求实数p 的取值范围.解:(1) 由121n n n a a a +=+,得11111111(1)222n n n n n na a a a a a ++--=-==-.又由123a =,得111102a -=≠.因此,1{1}n a -是以11112a -=为首项,以12为公比的等比数列.………5分(2)由(1)可得:111111()222n n na --=⨯=即221n n n a =+, 111221n n n a +++=+, 于是所求的问题:“对任意的n N +∈都有1n n a pa +<成立”可以等价于问题:“对任意的*N n ∈都有11111122122112122121n n n n n n n n n a p a ++++++++>=⋅==++++成立”.若记11()121n f n +=++,则()f n 显然是单调递减的, 故1116()(1)1215f n f +≤=+=+.所以,实数p 的取值范围为65p >.………………………12分19.(本小题满分12分)如图,在四棱锥P -ABCD 中,底面ABCD 为直角梯形,AD ∥BC ,90oBAD ∠=,PB ⊥平面ABCD ,CD ⊥BD ,PB =AB =AD =1,点E 在线段PA 上,且PE =2EA .(1)求证:PC ∥平面BDE ;(2)求二面角E -BD -A 的余弦值. 解:(1)法一:连AC ,交BD 于F ,连EF ,设法证明:1AE AF EP FC ==PBCE从而:EF ∥PC 故PC ∥平面BDE 法二:建立空间直角坐标系B-xyz ,如图, 求出点A 、D 、C 、E 、P 的坐标,再求出平面EBD 的法向量111(,,1)22n =-, 计算:10n PC ⋅=从而得到:PC ∥平面BDE(2)在空间直角坐标系中,由(1)得:平面EBD 的法向量111(,,1)22n =- 又平面ABD 的法向量2(0,0,1)n =所以1212126cos ,||||n n nn n n ⋅<>==⋅故二面角E -BD -A 的余弦值为20.(本小题满分13分)某单位设计一个展览沙盘,现欲在沙盘平面内,布设一个对角线在l 上的四边形电气 线路,如图所示. 为充分利用现有材料,边BC 、CD 用一根5米长的材料弯折而成; 边BA 、AD 用一根9米长的材料弯折而成. 要求A ∠和C ∠互补,且AB BC =. (1)设AB x =米,cos ()A f x =,求()f x 的解析式,并指出x 的取值范围;(2)求四边形ABCD 面积的最大值. 解:(1)ABD ∆中,由余弦定理:222222cos (9)2(9)cos BD AB AD AB AD Ax x x x A =+-⋅=+---又CBD ∆中,由余弦定理:222222cos (5)2(5)cos BD BC CD BC CD Cx x x x C =+-⋅=+---而A ∠和C ∠互补,∴cos cos A C =-DCBAl∴2222(9)2(9)cos (5)2(5)cos x x x x A x x x x C +---=+--- ⇒2cos A x =由2cos 1A x =<,∴25x <<故2cos A x =(25)x <<(2)11sin sin 22ABD ABCD BCD S S S AB AD A CB CD C ∆∆=+=⋅⋅+⋅⋅1[(9)sin (5)]2x x A x x sinC =⋅-+⋅-∵ A ∠和C ∠互补,∴sin A sinC = ∴((7)sin (7ABCD S x x A x x =-=-= 设22(7)(4)y x x =-- 25x << 则 2(7)(4)(21)y x x x '=--+∴ 当24x <<时,0y '>,y;当45x <<时,0y '<,y∴ 当4x =时,max 108y =故当4x =时,2max()S m ==21.(本小题满分13分)如图,在平面直角坐标系xOy 中,已知椭圆E :22221(0)x y a b a b +=>>的离心率e =, 12,A A 分别是椭圆E 的左、右两个顶点,圆2A 的半径为a ,过点1A 作圆2A 的切线,切点为P ,在x 轴的上方交椭圆E 于点Q . (1)求直线OP 的方程;(2)求1PQQA 的值;(3)设a 为常数.过点O 作两条互相垂直的直线,分别交椭圆E 于点,B C ,分别交 圆2A 于点,M N ,记OBC △和OMN △的面积分别为1S 、2S ,求12S S ⋅的最大值.解:⑴连结2A P ,则21A P A P ⊥,且2A P a =又122A A a =,所以1260A A P ∠=.所以260POA ∠=,所以直线OP 的方程为y .…………………………3分⑵ 由⑴知,直线2A P 的方程为)y x a =-,1A P 的方程为)y x a =+,联立解得2P ax =.因为e =,即c a =,所以2234c a =,2214b a =,故椭圆E 的方程为222241x y a a =+.由2222),41,y x a x y a a ⎧=+⎪⎪⎨⎪=⎪⎩+解得7Q a x =-, 所以1()3274()7a aPQ a QA a --==---. ………………………………………………8分⑶ 不妨设OM 的方程为(0)y kx k =>,联立方程组2222,41,y kx x y a a =⎧⎪⎨=⎪⎩+解得B ,所以OB = 用1k -代替上面的k ,得OC =.同理可得,OM =,ON =.所以41214S S OB OC OM ON a ⋅=⋅⋅⋅⋅=.15≤,当且仅当1k =时等号成立,所以12S S ⋅的最大值为45a . ……………………13分22. (本小题满分13分)已知函数3()ln ,()2a f x x g x x ==-(a 为实数).(1)当a =1时,求函数()()()x f x g x ϕ=-在[4,)x ∈+∞上的最小值;(2)若方程2()()f x e g x =(其中e 为自然对数的底)在区间1,12⎡⎤⎢⎥⎣⎦上有解,求实数a 的取值范围;(3)证明:[]1512(21)()(1)21460nk n f k f k f k n =+<+--+<+∑,n N *∈.解:(1)当1a =时,13()()()ln 2x f x g x x xϕ=-=+-,则'22111()x x x x x ϕ-=-=∵在区间(0,1]上,'()0x ϕ≤,在区间[1,+∞)上,'()0x ϕ≥∴()x ϕ在区间(0,1]上单调递减,在区间[1,+∞)上单调递增∴在x ∈[4,+∞)上,()x ϕ的最小值为5(4)ln 44ϕ=-. ………3分(2)∵方程2()()f x eg x =在区间1,12⎡⎤⎢⎥⎣⎦ 上有解即2ln 32x a e x =-在区间1,12⎡⎤⎢⎥⎣⎦上有解即332a x x =-在区间1,12⎡⎤⎢⎥⎣⎦ 上有解令33()2h x x x =-,x ∈1,12⎡⎤⎢⎥⎣⎦ ∴'23()32h x x =-∵在区间12⎡⎢⎣⎦ 上,'()0h x ≥,在区间⎤⎥⎣⎦ 上,'()0h x ≤ ∴()h x在区间1,22⎡⎢⎣⎦上单调递增,在区间2⎤⎥⎣⎦ 上单调递减, 又115(1),()228h h ==∴(1)()(2h h x h ≤≤即1()22h x ≤≤故1,22a ⎡∈⎢⎣⎦ ……………8分 (3)设2(21)()(1)k a f k f k f k =+--+24412ln(21)ln ln(1)ln(1)k k k k k k k ++=+--+=+由(1)知,()x ϕ的最小值为5(4)ln 404ϕ=->∴31ln 2x x >-(x≥4)又∵24414(1)k k k k ++>+22223(1)31441124412444151151144(21)44(21)(23)k k k k k a k k k k k k k +++-∴>-=-++++=+>++++5111()482123k k =+-++∴151111111( (4835572123)kk an n n =>+-+-++-++∑5111511151()()483234835460n n n n =+-≥+-=++构造函数)4(2ln )(≥+-=x x x x F ,则'1()xF x x -=,∴当4≥x 时,0)('<X F .∴)('X F 在[)+∞,4上单调递减,即0)12(ln 224ln )4()(<-=-=≤F x F 。
2013年湖南省高考数学试卷(理科)参考答案与试题解析一、选择题:本大题共8小题,每小题5分,共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.(5分)(2013•湖南)复数z=i•(1+i)(i为虚数单位)在复平面上对应的点位于()A.第一象限B.第二象限C.第三象限D.第四象限2.(5分)(2013•湖南)某校有男、女学生各500名,为了解男、女学生在学习兴趣与业余爱好方面是否存在显著差异,拟从全体学生中抽取100名学生进行调查,则宜采用的抽样方法是()A.抽签法B.随机数法C.系统抽样法D.分层抽样法分析:若总体由差异明显的几部分组成时,经常采用分层抽样的方法进行抽样解答:解:总体由男生和女生组成,比例为500:500=1:1,所抽取的比例也是1:1.故拟从全体学生中抽取100名学生进行调查,则宜采用的抽样方法是分层抽样法.故选D3.(5分)(2013•湖南)在锐角△ABC中,角A,B所对的边长分别为a,b.若2asinB=b,则角A等于()A.B.C.D.4.(5分)(2013•湖南)若变量x,y满足约束条件,则x+2y的最大值是()A.B.0C.D.5.(5分)(2013•湖南)函数f(x)=2lnx的图象与函数g(x)=x2﹣4x+5的图象的交点个数为()A.3B.2C.1D.06.(5分)(2013•湖南)已知,是单位向量,,若向量满足,则的取值范围为()A.B.C.D.点评:本题考查平面向量的数量积运算,根据题意作出图象,数形结合是解决本题的有力工具.7.(5分)(2013•湖南)已知棱长为1的正方体的俯视图是一个面积为1的正方形,则该正方体的正视图的面积不可能是()A.1B.C.D.8.(5分)(2013•湖南)在等腰直角三角形ABC中,AB=AC=4,点P是边AB边上异于AB的一点,光线从点P 出发,经BC,CA反射后又回到点P(如图1),若光线QR经过△ABC的重心,则AP等于()A.2B.1C.D.考点:与直线关于点、直线对称的直线方程.专题:直线与圆.分析:建立坐标系,设点P的坐标,可得P关于直线BC的对称点P1的坐标,和P关于y轴的对称点P2的坐标,由P1,Q,R,P2四点共线可得直线的方程,由于过△ABC的重心,代入可得关于a的方程,解之可得P 的坐标,进而可得AP的值.解答:解:建立如图所示的坐标系:可得B(4,0),C(0,4),故直线BC的方程为x+y=4,△ABC的重心为(,),设P(a,0),其中0<a<4,则点P关于直线BC的对称点P1(x,y),满足,解得,即P1(4,4﹣a),易得P关于y轴的对称点P2(﹣a,0),由光的反射原理可知P1,Q,R,P2四点共线,直线QR的斜率为k==,故直线QR的方程为y=(x+a),由于直线QR过△ABC的重心(,),代入化简可得3a2﹣4a=0,解得a=,或a=0(舍去),故P(,0),故AP=故选D点评:本题考查直线与点的对称问题,涉及直线方程的求解以及光的反射原理的应用,属中档题.二、填空题:本大题共8小题,考生作答7小题,第小题5分,共35分.(一)选做题(请考生在第9,10,11三题中任选两题作答、如果全做,则按前两题记分)(二)必做题(12~16题)9.(2013•湖南)在平面直角坐标系xOy中,若直线l:,(t为参数)过椭圆C:(θ为参数)的右顶点,则常数a的值为3.考点:参数方程化成普通方程;直线与圆锥曲线的关系.专题:圆锥曲线的定义、性质与方程.分析:直接划参数方程为普通方程得到直线和椭圆的普通方程,求出椭圆的右顶点,代入直线方程即可求得a的值.解答:解:由直线l:,得y=x﹣a,再由椭圆C:,得,①2+②2得,.所以椭圆C:的右顶点为(3,0).因为直线l过椭圆的右顶点,所以0=3﹣a,所以a=3.故答案为3.点评:本题考查了参数方程和普通方程的互化,考查了直线和圆锥曲线的关系,是基础题.10.(5分)(2013•湖南)已知a,b,c∈R,a+2b+3c=6,则a2+4b2+9c2的最小值为12.考点:柯西不等式;柯西不等式的几何意义.专题:计算题;不等式的解法及应用.分析:根据柯西不等式,得(a+2b+3c)2=(1×a+1×2b+1×3c)2≤(12+12+12)(a2+4b2+9c2)=3(a2+4b2+9c2),化简得a2+4b2+9c2≥12,由此可得当且仅当a=2,b=1,c=时,a2+4b2+9c2的最小值为12.解答:解:∵a+2b+3c=6,∴根据柯西不等式,得(a+2b+3c)2=(1×a+1×2b+1×3c)2≤(12+12+12)[a2+(2b)2+(3c)2]化简得62≤3(a2+4b2+9c2),即36≤3(a2+4b2+9c2)∴a2+4b2+9c2≥12,当且仅当a:2b:3c=1:1:1时,即a=2,b=1,c=时等号成立由此可得:当且仅当a=2,b=1,c=时,a2+4b2+9c2的最小值为12故答案为:12点评:本题给出等式a+2b+3c=6,求式子a2+4b2+9c2的最小值.着重考查了运用柯西不等式求最值与柯西不等式的等号成立的条件等知识,属于中档题.11.(5分)(2013•湖南)如图,在半径为的⊙O中,弦AB,CD相交于点P,PA=PB=2,PD=1,则圆心O到弦CD的距离为.考点:圆內接多边形的性质与判定;与圆有关的比例线段.专题:计算题.分析:首先利用相交弦定理求出CD的长,再利用勾股定理求出圆心O到弦CD的距离,注意计算的正确率.解答:解:由相交弦定理得,AP×PB=CP×PD,∴2×2=CP•1,解得:CP=4,又PD=1,∴CD=5,又⊙O的半径为,则圆心O到弦CD的距离为d===故答案为:.点评:此题主要考查了相交弦定理,垂径定理,勾股定理等知识,题目有一定综合性,是中考中热点问题.12.(5分)(2013•湖南)若,则常数T的值为3.考点:定积分.专题:计算题.分析:利用微积分基本定理即可求得.解答:解:==9,解得T=3,故答案为:3.点评:本题考查定积分、微积分基本定理,属基础题.13.(5分)(2013•湖南)执行如图所示的程序框图,如果输入a=1,b=2,则输出的a的值为9.考点:程序框图.专题:图表型.分析:分析程序中各变量、各语句的作用,再根据流程图所示的顺序,可知:该程序的作用是利用循环累加a值,并判断满足a>8时输出a的值.解答:解:程序在运行过程中各变量的聚会如下表示:是否继续循环 a b循环前/1 2第一圈是 3 2第二圈是 5 2第三圈是7 2第四圈是9 2第五圈否故最终输出的a值为9.故答案为:9.点评:根据流程图(或伪代码)写程序的运行结果,是算法这一模块最重要的题型,其处理方法是::①分析流程图(或伪代码),从流程图(或伪代码)中即要分析出计算的类型,又要分析出参与计算的数据(如果参与运算的数据比较多,也可使用表格对数据进行分析管理)⇒②建立数学模型,根据第一步分析的结果,选择恰当的数学模型③解模.14.(5分)(2013•湖南)设F1,F2是双曲线C:(a>0,b>0)的两个焦点,P是C上一点,若|PF1|+|PF2|=6a,且△PF1F2=30°的最小内角为30°,则C的离心率为.考点:双曲线的简单性质.专题:圆锥曲线的定义、性质与方程.分析:利用双曲线的定义求出|PF1|,|F1F2|,|PF2|,然后利用最小内角为30°结合余弦定理,求出双曲线的离心率.解答:解:因为F1、F2是双曲线的两个焦点,P是双曲线上一点,且满足|PF1|+|PF2|=6a,不妨设P是双曲线右支上的一点,由双曲线的定义可知|PF1|﹣|PF2|=2a所以|F1F2|=2c,|PF1|=4a,|PF2|=2a,∵△PF1F2的最小内角∠PF1F2=30°,由余弦定理,∴|PF2|2=|F1F2|2+|PF1|2﹣2|F1F2||PF1|cos∠PF1F2,即4a2=4c2+16a2﹣2c×4a×,∴c2﹣2ca+3a2=0,∴c= a所以e==.故答案为:.点评:本题考查双曲线的定义,双曲线的离心率的求法,考查计算能力.15.(5分)(2013•湖南)设S n为数列{a n}的前n项和,,n∈N*,则(1)a3=﹣;(2)S1+S2+…+S100=.考点:数列的求和;数列的函数特性.专题:等差数列与等比数列.分析:(1)把给出的数列递推式先分n=1和n≥2讨论,由此求出首项和n≥2时的关系式.对此关系式再分n为偶数和奇数分别得到当n为偶数和奇数时的通项公式,则a3可求;(2)把(1)中求出的数列的通项公式代入,n∈N*,则利用数列的分组求和和等比数列的前n项和公式可求得结果.解答:解:由,n∈N*,当n=1时,有,得.当n≥2时,.即.若n为偶数,则.所以(n为正奇数);若n为奇数,则=.所以(n为正偶数).所以(1).故答案为﹣;(2)因为(n为正奇数),所以﹣,又(n为正偶数),所以.则.,.则.….所以,S1+S2+S3+S4+…+S99+S100====.故答案为.点评:本题考查了数列的求和,考查了数列的函数特性,解答此题的关键在于当n为偶数时能求出奇数项的通项,当n为奇数时求出偶数项的通项,此题为中高档题.16.(5分)(2013•湖南)设函数f(x)=a x+b x﹣c x,其中c>a>0,c>b>0.(1)记集合M={(a,b,c)|a,b,c不能构成一个三角形的三条边长,且a=b},则(a,b,c)∈M所对应的f(x)的零点的取值集合为{x|0<x≤1}.(2)若a,b,c是△ABC的三条边长,则下列结论正确的是①②③.(写出所有正确结论的序号)①∀x∈(﹣∞,1),f(x)>0;②∃x∈R,使a x,b x,c x不能构成一个三角形的三条边长;③若△ABC为钝角三角形,则∃x∈(1,2),使f(x)=0.考点:命题的真假判断与应用;函数的零点;进行简单的合情推理.专题:阅读型.分析:(1)由集合M中的元素满足的条件,得到c≥a+b=2a,求得的范围,解出函数f(x)=a x+b x﹣c x的零点,利用不等式可得零点x的取值集合;(2)对于①,把函数式f(x)=a x+b x﹣c x变形为,利用指数函数的单调性即可证得结论成立;对于②,利用取特值法说明命题是正确的;对于③,由△ABC为钝角三角形说明f(2)<0,又f(1)>0,由零点的存在性定理可得命题③正确.解答:解:(1)因为c>a,由c≥a+b=2a,所以,则.令f(x)=a x+b x﹣c x=.得,所以.所以0<x≤1.故答案为{x|0<x≤1};(2)因为,又,所以对∀x∈(﹣∞,1),.所以命题①正确;令x=1,a=b=1,c=2.则a x=b x=1,c x=2.不能构成一个三角形的三条边长.所以命题②正确;若三角形为钝角三角形,则a2+b2﹣c2<0.f(1)=a+b﹣c>0,f(2)=a2+b2﹣c2<0.所以∃x∈(1,2),使f(x)=0.所以命题③正确.故答案为①②③.点评:本题考查了命题真假的判断与应用,考查了函数零点的判断方法,训练了特值化思想方法,解答此题的关键是对题意的正确理解,此题是中档题.三、解答题:本大题共6小题,共75分.解答应写出文字说明、证明过程或演算步骤.17.(12分)(2013•湖南)已知函数,.(I)若α是第一象限角,且,求g(α)的值;(II)求使f(x)≥g(x)成立的x的取值集合.考点:两角和与差的正弦函数;两角和与差的余弦函数;二倍角的余弦;正弦函数的单调性.专题:计算题;三角函数的图像与性质.分析:(I)根据两角和与差的三角函数公式化简,得f(x)=sinx,结合解出sinα=,利用同角三角函数的基本关系算出cosα=.由二倍角的余弦公式进行降次,可得g(x)=1﹣cosx,即可算出g(α)=1﹣cosα=;(II)f(x)≥g(x),即sinx≥1﹣cosx,移项采用辅助角公式化简整理,得2sin(x+)≥1,再根据正弦函数的图象与性质,即可求出使f(x)≥g(x)成立的x的取值集合.解答:解::∵sin(x﹣)=sinxcos﹣cosxsin=sinx﹣cosxcos(x﹣)=cosxcos+sinxsin=cosx+sinx∴=(sinx﹣cosx)+(cosx+sinx)=sinx而=1﹣cosx(I)∵,∴sinα=,解之得sinα=∵α是第一象限角,∴cosα==因此,g(α)==1﹣cosα=,(II)f(x)≥g(x),即sinx≥1﹣cosx移项,得sinx+cosx≥1,化简得2sin(x+)≥1∴sin(x+)≥,可得+2kπ≤x+≤+2kπ(k∈Z)解之得2kπ≤x≤+2kπ(k∈Z)因此,使f(x)≥g(x)成立的x的取值集合为{x|2kπ≤x≤+2kπ(k∈Z)}点评:本题给出含有三角函数的两个函数f(x)、g(x),求特殊函数值并讨论使f(x)≥g(x)成立的x的取值集合.着重考查了三角恒等变换、同角三角函数的基本关系和三角函数的图象与性质等知识,属于中档题.18.(12分)(2013•湖南)某人在如图所示的直角边长为4米的三角形地块的每个格点(指纵、横直线的交叉点以及三角形顶点)处都种了一株相同品种的作物.根据历年的种植经验,一株该种作物的年收获Y(单位:kg)与它的“相近”作物株数X之间的关系如下表所示:X 1 2 3 4Y 51 48 45 42这里,两株作物“相近”是指它们之间的直线距离不超过1米.(I)从三角形地块的内部和边界上分别随机选取一株作物,求它们恰好“相近”的概率;(II)在所种作物中随机选取一株,求它的年收获量的分布列与数学期望.考点:离散型随机变量及其分布列;古典概型及其概率计算公式;离散型随机变量的期望与方差.专题:概率与统计.分析:(I)确定三角形地块的内部和边界上的作物株数,分别求出基本事件的个数,即可求它们恰好“相近”的概率;(II)确定变量的取值,求出相应的概率,从而可得年收获量的分布列与数学期望.解答:解:(I)所种作物总株数N=1+2+3+4+5=15,其中三角形地块内部的作物株数为3,边界上的作物株数为12,从三角形地块的内部和边界上分别随机选取一株的不同结果有=36种,选取的两株作物恰好“相近”的不同结果有3+3+2=8,∴从三角形地块的内部和边界上分别随机选取一株作物,求它们恰好“相近”的概率为=;(II)先求从所种作物中随机选取一株作物的年收获量为Y的分布列∵P(Y=51)=P(X=1),P(48)=P(X=2),P(Y=45)=P(X=3),P(Y=42)=P(X=4)∴只需求出P(X=k)(k=1,2,3,4)即可记n k为其“相近”作物恰有k株的作物株数(k=1,2,3,4),则n1=2,n2=4,n3=6,n4=3由P(X=k)=得P(X=1)=,P(X=2)=,P(X=3)==,P(X=4)==∴所求的分布列为Y 51 48 45 42P数学期望为E(Y)=51×+48×+45×+42×=46点评:本题考查古典概率的计算,考查分布列与数学期望,考查学生的计算能力,属于中档题.19.(12分)(2013•湖南)如图,在直棱柱ABCD﹣A1B1C1D1中,AD∥BC,∠BAD=90°,AC⊥BD,BC=1,AD=AA1=3.(I)证明:AC⊥B1D;(II)求直线B1C1与平面ACD1所成的角的正弦值.考点:直线与平面所成的角;直线与平面垂直的性质.专题:计算题;证明题;空间位置关系与距离;空间角.分析:(I)根据直棱柱性质,得BB1⊥平面ABCD,从而AC⊥BB1,结合BB1∩BD=B,证出AC⊥平面BB1D,从而得到AC⊥B1D;(II)根据题意得AD∥B1C1,可得直线B1C1与平面ACD1所成的角即为直线AD与平面ACD1所成的角.连接A1D,利用线面垂直的性质与判定证出AD1⊥平面A1B1D,从而可得AD1⊥B1D.由AC⊥B1D,可得B1D⊥平面ACD,从而得到∠ADB1与AD与平面ACD1所成的角互余.在直角梯形ABCD中,根据Rt△ABC∽Rt△DAB,算出AB=,最后在Rt△AB1D中算出B1D=,可得cos∠ADB1=,由此即可得出直线B1C1与平面ACD1所成的角的正弦值.解答:解:解:(I)∵BB1⊥平面ABCD,AC⊂平面ABCD,∴AC⊥BB1,又∵AC⊥BD,BB1、BD是平面BB1D内的相交直线∴AC⊥平面BB1D,∵B1D⊂平面BB1D,∴AC⊥B1D;(II)∵AD∥BC,B1C1∥BC,∴AD∥B1C1,由此可得直线B1C1与平面ACD1所成的角,等于直线AD与平面ACD1所成的角(记为θ)连接A1D,∵直棱柱ABCD﹣A1B1C1D1中,∠BAD=∠B1A1D1=90°,∴B1A1⊥平面A1D1DA,结合AD1⊂平面A1D1DA,得B1A1⊥AD1又∵AD=AA1=3,∴四边形A1D1DA是正方形,可得AD1⊥A1D∵B1A1、A1D是平面A1B1D内的相交直线,∴AD1⊥平面A1B1D,可得AD1⊥B1D,由(I)知AC⊥B1D,结合AD1∩AC=A可得B1D⊥平面ACD,从而得到∠ADB1=90°﹣θ,∵在直角梯形ABCD中,AC⊥BD,∴∠BAC=∠ADB,从而得到Rt△ABC∽Rt△DAB因此,,可得AB==连接AB1,可得△AB1D是直角三角形,∴B1D2=B1B2+BD2=B1B2+AB2+BD2=21,B1D=在Rt△AB1D中,cos∠ADB1===,即cos(90°﹣θ)=sinθ=,可得直线B1C1与平面ACD1所成的角的正弦值为.点评:本题给出直四棱柱,求证异面直线垂直并求直线与平面所成角的正弦之值,着重考查了直四棱柱的性质、线面垂直的判定与性质和直线与平面所成角的定义等知知识,属于中档题.20.(13分)(2013•湖南)在平面直角坐标系xOy中,将从点M出发沿纵、横方向到达点N的任一路径称为M到N的一条“L路径”.如图所示的路径MM1M2M3N与路径MN1N都是M到N的“L路径”.某地有三个新建居民区,分别位于平面xOy内三点A(3,20),B(﹣10,0),C(14,0)处.现计划在x轴上方区域(包含x轴)内的某一点P处修建一个文化中心.(I)写出点P到居民区A的“L路径”长度最小值的表达式(不要求证明);(II)若以原点O为圆心,半径为1的圆的内部是保护区,“L路径”不能进入保护区,请确定点P的位置,使其到三个居民区的“L路径”长度之和最小.考点:根据实际问题选择函数类型;绝对值三角不等式.专题:应用题;不等式的解法及应用.分析:(I)根据“L路径”的定义,可得点P到居民区A的“L路径”长度最小值;(II)由题意知,点P到三个居民区的“L路径”长度之和的最小值为点P到三个居民区的“L路径”长度最小值之和(记为d)的最小值,分类讨论,利用绝对值的几何意义,即可求得点P的坐标.解答:解:设点P的坐标为(x,y),则(I)点P到居民区A的“L路径”长度最小值为|x﹣3|+|y﹣20|,y∈[0,+∞);(II)由题意知,点P到三个居民区的“L路径”长度之和的最小值为点P到三个居民区的“L路径”长度最小值之和(记为d)的最小值①当y≥1时,d=|x+10|+|x﹣14|+|x﹣3|+2|y|+|y﹣20|∵d1(x)=|x+10|+|x﹣14|+|x﹣3|≥|x+10|+|x﹣14|≥24∴当且仅当x=3时,d1(x)=|x+10|+|x﹣14|+|x﹣3|的最小值为24∵d2(y)=2|y|+|y﹣20|≥21∴当且仅当y=1时,d2(y)=2|y|+|y﹣20|的最小值为21∴点P的坐标为(3,1)时,点P到三个居民区的“L路径”长度之和的最小,且最小值为45;②当0≤y≤1时,由于“L路径”不能进入保护区,∴d=|x+10|+|x﹣14|+|x﹣3|+1+|1﹣y|+|y|+|y﹣20|此时d1(x)=|x+10|+|x﹣14|+|x﹣3|,d2(y)=1+|1﹣y|+|y|+|y﹣20|=22﹣y≥21由①知d1(x)=|x+10|+|x﹣14|+|x﹣3|≥24,∴d1(x)+d2(y)≥45,当且仅当x=3,y=1时等号成立综上所述,在点P(3,1)处修建文化中心,可使该文化中心到三个居民区的“L路径”长度之和最小.点评:本题考查新定义,考查分类讨论的数学思想,考查学生建模的能力,同时考查学生的理解能力,属于难题.21.(13分)(2013•湖南)过抛物线E:x2=2py(p>0)的焦点F作斜率率分别为k1,k2的两条不同直线l1,l2,且k1+k2=2.l1与E交于点A,B,l2与E交于C,D,以AB,CD为直径的圆M,圆N(M,N为圆心)的公共弦所在直线记为l.(I)若k1>0,k2>0,证明:;(II)若点M到直线l的距离的最小值为,求抛物线E的方程.考点:直线与圆锥曲线的关系;平面向量数量积的运算;抛物线的标准方程.专题:圆锥曲线的定义、性质与方程.分析:(Ⅰ)由抛物线方程求出抛物线的焦点坐标,写出两条直线的方程,由两条直线方程和抛物线方程联立求出圆M和圆N的圆心M和N的坐标,求出向量和的坐标,求出数量积后转化为关于k1和k2的表达式,利用基本不等式放缩后可证得结论;(Ⅱ)利用抛物线的定义求出圆M和圆N的直径,结合(Ⅰ)中求出的圆M和圆N的圆心的坐标,写出两圆的方程,作差后得到两圆的公共弦所在直线方程,由点到直线的距离公式求出点M到直线l的距离,利用k1+k2=2转化为含有一个未知量的代数式,配方后求出最小值,由最小值等于求出p的值,则抛物线E的方程可求.解答:解:(I)由题意,抛物线E的焦点为,直线l1的方程为.由,得.设A,B两点的坐标分别为(x1,y1),(x2,y2),则x1,x2是上述方程的两个实数根.从而x1+x2=2pk1,.所以点M的坐标为,.同理可得点N的坐标为,.于是.由题设k1+k2=2,k1>0,k2>0,k1≠k2,所以0<.故.(Ⅱ)由抛物线的定义得,,所以,从而圆M的半径.故圆M的方程为,化简得.同理可得圆N的方程为于是圆M,圆N的公共弦所在的直线l的方程为.又k2﹣k1≠0,k1+k2=2,则l的方程为x+2y=0.因为p>0,所以点M到直线l的距离为=.故当时,d取最小值.由题设,解得p=8.故所求抛物线E的方程为x2=16y.点评:本题考查了抛物线的标准方程,考查了平面向量数量积的运算,考查了直线与圆锥曲线的关系,直线与圆锥曲线联系在一起的综合题在高考中多以高档题、压轴题出现,主要涉及位置关系的判定,弦长问题、最值问题、对称问题、轨迹问题等.突出考查了数形结合、分类讨论、函数与方程、等价转化等数学思想方法.属难题.22.(13分)(2013•湖南)已知a>0,函数.(I)记f(x)在区间[0,4]上的最大值为g(a),求g(a)的表达式;(II)是否存在a使函数y=f(x)在区间(0,4)内的图象上存在两点,在该两点处的切线互相垂直?若存在,求出a的取值范围;若不存在,请说明理由.考点:利用导数求闭区间上函数的最值;利用导数研究曲线上某点切线方程.专题:导数的综合应用.分析:(I)利用绝对值的几何意义,分类讨论,结合导数确定函数的单调性,从而可得g(a)的表达式;(II)利用曲线y=f(x)在两点处的切线互相垂直,建立方程,从而可转化为集合的运算,即可求得结论.解答:解:(I)当0≤x≤a时,;当x>a时,∴当0≤x≤a时,,f(x)在(0,a)上单调递减;当x>a时,,f(x)在(a,+∞)上单调递增.①若a≥4,则f(x)在(0,4)上单调递减,g(a)=f(0)=②若0<a<4,则f(x)在(0,a)上单调递减,在(a,4)上单调递增∴g(a)max={f(0),f(4)}∵f(0)﹣f(4)==∴当0<a≤1时,g(a)=f(4)=;当1<a<4时,g(a)=f(0)=,综上所述,g(a)=;(II)由(I)知,当a≥4时,f(x)在(0,4)上单调递减,故不满足要求;当0<a<4时,f(x)在(0,a)上单调递减,在(a,4)上单调递增,若存在x1,x2∈(0,4)(x1<x2),使曲线y=f(x)在两点处的切线互相垂直,则x1∈(0,a),x2∈(a,4),且f′(x1)f′(x2)=﹣1∴•=﹣1∴①∵x1∈(0,a),x2∈(a,4),∴x1+2a∈(2a,3a),∈(,1)∴①成立等价于A=(2a,3a)与B=(,1)的交集非空∵,∴当且仅当0<2a<1,即时,A∩B≠∅综上所述,存在a使函数y=f(x)在区间(0,4)内的图象上存在两点,在该两点处的切线互相垂直,且a 的取值范围是(0,).点评:本题考查导数知识的运用,考查分类讨论的数学思想,考查学生分析解决问题的能力,正确分类是关键.。
湖南省2013届高三数学名校联考试题(3)时量:120分钟;满分:150分一、选择题:本大题共9小题,每小题5分,满分45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31ii+(i 为虚数单位)在复平面内所对应的点在 A.第一象限 B.第二象限 C.第三象限 D.第四象限 2.下列命题中的假命题是A.0lg ,=∈∃x R xB.1tan ,=∈∃x R xC.0,2>∈∀x R x D.02,>∈∀xR x 3.已知x 与y 之间的一组数据: 则关于y 与x 的线性回归方程a bx y +=必过定点A.(2,2)B.(1.5,0)C.(1,2)D.(1.5,4) 4.设)2(,53sin παπα<<=,21)tan(=-βπ,则=-)tan(βα A.72- B.52- C.112- D.211-5.下图是一个把二进制数)2(11111化成十进制数的程序框图,判断框内需填入的条件是 A.4>i B.3≤i C.3>i D.4≤i6.若等比数列}{n a 的前n 项和23-⋅=nn a S ,则=2aA.4B.12C.24D.36 7.若圆09422=--+x y x 与y 轴的两个交点A 、B 都在双曲线上,且A 、B 两点恰好将 此双曲线的焦距三等分,则此双曲线的标准方程为A.172922=-y x B.172922=-x y C.1811622=-y x D.1168122=-x y 8.已知一个几何体的三视图如图所示,则该几何体外接球的表面积为 A.193πB.43πC.1912πD.163π x 0 1 2 3 y1 3579.已知函数xe xf =)(,则当21x x <时,下列结论 正确的是 A.2121)()(1x x x f x f ex -->B.2121)()(1x x x f x f e x++<C.2121)()(2x x x f x f ex -->D.2121)()(2x x x f x f e x++<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.把答案填在答题卡中对应题号后的横线上.(一)选做题(请在第10,11两题中任选一题作答,如果全做,则按前一题记分) 10.(优选法与试验设计初步)用分数法对[]105,0区间段进行优选法试验,若将此区间段均 分为21等分,则第一个试点为_______.11.(极坐标与参数方程)在极坐标系中,已知曲线C 的方程是θρsin 4=,过点)6,4(π作曲线C 的切线,则切线长等于 . (二)必做题(12~16题)12.已知全集R U =,}03|{2<+=x x x A ,}1|{-<=x x B ,则=)(B A C U . 13.若⎩⎨⎧≥≤||1x y y ,则y x 3+的最大值是_________.14.如图所示,已知点G 是ABC ∆的重心,过G 作直线与AB ,AC 两边分别交于M 、N 两 点,且,,AC y AN AB x AM ==则yx xy+的值为________.15.设|2|)(2x x f -=,若b a <<0,满足)()(b f a f =,则ab 的取值范围是 . 16.在边长为2的正方形ABCD 内部任取一点M . ⑴满足90>∠AMB 的概率为__________. ⑵满足 135>∠AMB 的概率为_________.ABCGM N三、解答题:本大题共6小题,共75分. 解答应写出文字说明,证明过程或推演步骤. 17.(本小题满分12分)如图,位于A 处的信息中心获悉:在其正东方向相距40海里的B 处有一艘渔船遇险,在原地等待营救.信息中心立即把消息告知在其南偏西030且相距20海里的C 处的乙船,现乙船朝北偏东θ的方向沿直线CB 前往B 处救援.⑴求线段CB 的长度及ACB ∠sin 的值; ⑵求θcos 的值.18.(本小题满分12分)衡阳市第一次联考后,某校对甲、乙两个文科班的数学考试成绩进行分析,规定:大于或等于120分为优秀,120分以下为非优秀.统计成绩后,得到如下的22⨯列联表,且已知在甲、乙两个文科班全部110人中随机抽取1人为优秀的概率为113. 优秀 非优秀合计甲班 10乙班 30合计110⑴请完成上面的列联表;⑵根据列联表的数据,若按99.9%的可靠性要求,能否认为“成绩与班级有关系”; ⑶若按下面的方法从甲班优秀的学生中抽取一人:把甲班优秀的10名学生从2到11进行编号,先后两次抛掷一枚均匀的骰子,出现的点数之和为被抽取人的序号.试求抽到9号或10号的概率.参考公式与临界值表:))()()(()(22d b c a d c b a bc ad n K ++++-=.)(2k K P ≥0.100 0.050 0.025 0.010 0.001 k2.7063.8415.0246.63510.82840东30A B20 北CFCDAB E19.(本小题满分12分)如图,已知AB ⊥平面ACD ,DE ⊥平面ACD ,△ACD 为等边三角形,AD =DE =2AB ,F 为CD 的中点.⑴求证://AF 平面BCE ;⑵求证:平面CDE ⊥平面BCE ; ⑶求BF 与平面BCE 所成角的正弦值.20.(本小题满分13分)在平面直角坐标系xOy 中,设点),(y x P ,)4,(-x M ,以线段PM 为直径的圆过原点O . ⑴求动点P 的轨迹W 的方程;⑵过点)4,0(-E 的直线l 与轨迹W 交于A 、B 两点,点A 关于y 轴的对称点为A ',试判断直线B A '是否恒过一定点,并证明你的结论.21.(本小题满分13分)已知点列),1(11y B ,),2(22y B ,…,),(n n y n B ,)(*∈N n 顺次为一次函数814+=x y 图像上的点,点列)0,(11x A ,)0,(22x A ,…,)0,(n n x A ,)(*∈N n 顺次为x 轴正半轴上的点,其中)10(,1<<=a a x .对于任意*∈N n ,点n A 、n B 、1+n A 构成以n B 为顶点的等腰三角形.⑴求}{n y 的通项公式,并证明}{n y 是等差数列;⑵试判断n n x x -+2是否为同一常数(不必证明),并求出数列}{n x 的通项公式; ⑶在上述等腰三角形1+n n n A B A 中,是否存在直角三角形?若有,求出此时a 的值;若不存在,请说明理由.22.(本小题满分13分)已知函数x b ax x f ln |2|)(+-=,)0(>x .⑴若1=a ,)(x f 在),0(+∞上是单调增函数,求b 的取值范围; ⑵若2≥a ,1=b ,求方程xx f 1)(=在]1,0(上解的个数.答案及评分标准一、选择题: 1. B 解析:i iii i +-=-+=+1113,故选B. 2. C 解析:当0=x 时,02=x ,故选C.3. D 解析:回归方程必过样本中心点),(y x ,故选D.4. C 解析:53sin =α ,43tan -=α;21tan -=β , =-∴)tan(βα112tan tan 1tan tan -=+-βαβα,故选C.5. A 解析:3121212121211111101234)2(=⨯+⨯+⨯+⨯+⨯=,故选A. 6. B 解析:{}n a 为等比数列,2=∴a ,又12122=-=S S a ,故选B. 7. B 解析:由09422=--+x y x ,令x =0得3±=y .设双曲线方程为12222=-b x a y ,3=a ,且9322=⇒=c ca .故72222=-=a c b ,故选B.8. A 解析:由三视图可知几何体为正三棱柱,底边长为2,高为1,外接球半径22)332()21(+=r =1219,ππ31942==∴r S ,故选 A.9. C 解析:设))(,()),(,(2211x f x B x f x A ,则2xe 表示曲线xe xf =)(在B 点处的切线的斜率,而2121)()(x x x f x f --表示直线AB 的斜率,由数形结合可知:2xe >2121)()(x x x f x f --,故选 C.二、填空题:10.65 解析:第一试点为65)0105(2113=-⨯. 11.22 解析:曲线C 方程可化为y y x 422=+,表示圆、圆心)2,0(,半径2=r ,点)6,4(π的直角坐标为)2,32(,所以切线长为222)32(-22=.12.(][)+∞-⋃-∞-,13, 解析:}03|{<<-=x x A ,}1|{-<=x x B . (][)+∞-⋃-∞-=⋂∴,13,)(B A C U . 13. 4 解析:作可行域,如图所示阴影区域,令y x z 3+=,yBAxO当直线l :y x z 3+=经过点)1,1(B 时,4m ax =Z .14.31 解析:G 为重心,)(31AC AB AG +=∴,又G N M ,, 三点共线,GN MG λ=∴.即)(AG AN AM AG -=-λAN AM AG λλ+=+⇒)1(,AC y AB x AC AB +=++∴)(31λ, 3131313131=⎪⎩⎪⎨⎧⎪⎩⎪⎨⎧+⇒+=+=⇒=+=+∴y x xy y x y x λλλλλλ. 15.)2,0( 解析:|2|)(2x x f -= 的图像关于y 轴对称,b a <<0且)()(b f a f =,b a <<<∴20,由)()(b f a f =得:4,222222=+∴-=-b a b a .42<∴ab ,20<<∴ab .16.⑴8π 解析:以AB 为直径作圆,当M 在圆与正方形围成的半圆内时,90>∠AMB . 所求概率为842ππ==P .⑵82-π 解析:在边AB 的垂直平分线上,正方形ABCD 外部取点O ,以O 为圆心,OA=2为半径作圆,当点M 位于正方形与圆围成的弓形内时,135>∠AMB ,故所求概率8241221)2(42-=⨯⨯-⨯=ππP . 三、解答题:17.解:⑴如图所示,在ABC ∆中,0120,20,40=∠==BAC AC AB ,2800120cos 20222=⋅⋅-+=∴AC AB AC AB BC720=∴BC . ……3分721sin sin sin sin =∠⋅=∠⇒∠=∠BC BAC AB ACB BAC BC ACB AB. ……6分 ⑵0120=∠BAC ,)60,0(0∈∠∴ACB .772s i n 1c o s 2=∠-=∠∴A C B A C B . ……9分 030+∠=ACB θ , 1421)30cos(cos 0=+∠=∴ACB θ. ……12分 18.解析:⑴优秀非优秀合计甲班 10 50 60 乙班 20 30 50 合计30 80 110………………3分⑵根据列联表中的数据,得到.828.10487.780305060)50203010(11022<≈⨯⨯⨯⨯-⨯=K因此按%9.99的可靠性要求,不能认为“成绩与班级有关系”. ………7分 ⑶设“抽到9或10号”为事件A ,先后两次抛掷一枚均匀的骰子,出现的点数 为),(y x .所有的基本事件有:)1,1(、)2,1(、)3,1(、 、)6,6(共36个. …………9分 事件A 包含的基本事件有:)6,3(、)5,4(、)4,5(、)3,6(、)5,5(、)6,4()4,6(共7个. ……11分所以367)(=A P ,即抽到9号或10号的概率为367. …………12分 19.解:⑴取CE 的中点G ,连BG ,FG.又因F 为CD 的中点,∴FG //DE 21, ……………1分 又 AB ⊥平面ACD ,DE ⊥平面ACD ,∴BA //DE 21. ……………2分∴BA //FG , 四边形ABGF 为平行四边形,故BG//AF. ……………3分又⊆BG 面BCE,⊄AF 面BCE//AF ∴平面BCE . ……………4分 ⑵因△ABC 为等边三角形,F 为CD 的中点,∴AF ⊥CD.又 DE ⊥平面ACD ,AF ⊆面ABC, ∴DE ⊥AF. ……………6分 ∴AF ⊥面CDE , ……………7分又 BG//AF ,∴BG ⊥面CDE.又BG ⊆面BCE ,∴平面CDE ⊥平面BCE . ……………8分⑶过F 作FH 垂直CE 于H,连接BH.平面CDE ⊥平面BCE ,∴FH ⊥平面BCE.∴∠FBH 为BF 与平面BCE 所成的角. ……………10分 设AD=a 2,则AB=a , AF=a 3,在直角△BAF 中,BF=a 2. 又△CDE 为等腰直角三角形,∴∠DCE=45.在等腰Rt △CHF 中,FH=a CF 2222=, 在Rt △FHB 中,sin ∠FBH=42=BF FH . ∴BF 与平面BCE 所成的角的正弦值为42. ……………12分 20.解:⑴由题意可得OM OP ⊥,0=⋅OM OP . ………….2分即:0)4,(),(=-⋅x y x , ………….3分.042=-∴y x ………….4分即动点的轨迹方程为.42y x = ………….5分 ⑵设直线l 的方程为4-=kx y , …………..6分 令),(),,(2211y x B y x A ,则),(11y x A -'. …………..7分⎩⎨⎧=-=yx kx y 442 ,消去y 整理得:,01642=+-kx x …………..8分 ,064162>-=∆∴k 即2||>k .且.16,42121==+x x k x x …………..9分∴直线),(:212122x x x x y y y y B A -+-=-' …………….10分∴221212)(y x x x x y y y +-+-=22212212241)()(4x x x x x x x +-+-= 222122124144x x x x x x x +---=442112x x x x x +-=4412+-=x x x ….12分∴直线B A '恒过定点)4,0(. …………13分21.解:⑴8141+=n y n ,41)8141(81)1(411=+-++=-∴+n n y y n n . }{n y ∴是首项为83,公差为等41差数列; ……………..3分⑵22=-+n n x x 为常数,12531,,,,-∴n x x x x 及n x x x x 2642,,,, 都是公差为2的等差数列. …..4分 ,22)1(2112a n n x x n +-=-+=∴-.2222)1(222a n n a n x x n -=-+-=-+= ……………..6分⎩⎨⎧--+=∴为正偶数为正奇数n a n n a n x n ,,1. ……………..7分⑶要使1+n n n A B A 为直角三角形,则)814(22||1+==+n y A A n n n , )814(21+=-∴+n x x n n . ……………..8分当n 为正奇数时,,1,11-+=-+=+a n x a n x n n ).1(21a x x n n -=-∴+))(10(487)814(2)1(2*<<-=⇒+=-∴a n ,na n a 为奇数,取.5;81,3;851)式无解则(*≥===⇒=n a n a n ……………..10分当n 为正偶数时,,,1a n x a n x n n -=+=+.21a x x n n =-∴+))(10(814)814(22*<<+=⇒+=∴a n n a n a 为偶数, 取2=n ,得.,4.85)式无解则(若*≥=n a ……………..12分 综上可知,存在满足题意的直角三角形,此时a 的值为.85,81 ……………..13分 22.解:⑴1=a⎩⎨⎧≥+-<<++-=+-=∴)2(,ln 2)20(,ln 2ln |2|)(x x b x x x b x x b x x f . ………..1分 ①当20<<x 时,x b x x f ln 2)(++-=,x b x f +-='∴1)(. 01≥+-∴xb 恒成立x b ≥⇔恒成立2≥⇔b . ………..3分 ②当2≥x 时,x b x x f ln 2)(+-=,x b x f +='∴1)(.01≥+∴xb 恒成立x b -≥⇔恒成立2-≥⇔b . ………..5分又)(x f 在x=2处连续 ),2[+∞∈∴b . ………..6分 ⑵设xx ax x g 1ln |2|)(-+-=, ⎪⎩⎪⎨⎧≥-+-<<-++-=∴)2(,1ln 2)20(,1ln 2)(a x x x ax a x x x ax x g . ………..7分 ①当a x 20<<时,x x ax x g 1ln 2)(-++-=,211)(xx a x g ++-='∴. a x 20<< ,21a x >∴. 04)2(42)(2≥-=++->'∴a a a a a x g . )(x g ∴在)2,0(a上是增函数. ………..9分 ②当a x 2≥时,x x ax x g 1ln 2)(-+-=,011)(2>++='∴xx a x g . )(x g ∴在),2(+∞a上是增函数. ………..10分 )(x g 在ax 2=连续, )(x g ∴在),0(+∞上是增函数. ………..11分22ln )2(a a a g -= ,而2≥a ,02ln ≤∴a ,即0)2(<ag .3)1(-=a g ,3≥∴a 时,03)1(≥-=a g 0)(=∴x g 在]1,0(上有惟一解. ……..12分 32<≤a 时,03)1(<-=a g 0)(=∴x g 在]1,0(上无解. ……..13分。
湖南省株洲市二中2013届高三数学第七次月考试题 文时量120分钟 分数150分一、选择题:本大题共9小题,每小题5分,共45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.i 是虚数单位,则复数1ii+的虚部是 ( )A .1B .-1C .12D .12-2. 已知等差数列{}241071510S n a a a ==中,,,则前项和=( ) A .420 B .380 C .210 D .140 3.已知3(,),sin ,25παπα∈=则tan()4πα+等于 ( ) A .17 B. 7 C. 17- D. 7- 4.若一几何体的正视图与侧视图均为边长是1的正方形,则下列图形一定不是该几何体的俯视图的是( )5. 一个算法的程序框图如右图所示,若输出的结A.?98≤iB. ?99≤iC. ?001≤iD.?101≤i6.设56)(2+-=x x x f ,且实数x 、y 满足条件⎩⎨⎧≤≤≥-;51,0)()(x y f x f 则x y 的最大值是( ) A .549-B .3C .4D .57. 函数()s i n ()(0,0,||)2f x A x A πωϕωϕ=+>><满足(1)0f =,则( )A .(1)f x -一定是偶函数B .(1)f x -一定是奇函数C .(1)f x +一定是偶函数D .(1)f x +一定是奇函数8. 已知函数 对任意自然数 均满足:22)]([2)()(y f x f y x f +=+且0)1(≠f ,则)2120(f 等于 ( )A .2011B .2012C .1006D .10059.已知直线2-=x y 与圆03422=+-+x y x 及抛物线x y 82=依 次交于D C B A 、、、四点,则||||CD AB +等于 ( )A.10B.12C.14D.16二、填空题:本大题共6小题,每小题5分,共30分,把答案填在答题卡中相应的横线上. (一)选做题(请考生在第10、11两题中任选一题作答,如果全做,则按前一题记分) 10.已知一种材料的最佳加入量是100g 至200g 之间,现有三次加入机会, 若按分数法优选,则第一次与第二次试点的加入量分别是 11.(极坐标与参数方程)在同一直角坐标系中,若曲线2cos :2sin x m C y αα=+⎧⎨=⎩(α为参数)与曲线24:32x tD y t =-⎧⎨=-⎩(t 为参数) 没有公共点,则实数m 的取值范围是 。
株洲市二中2013届高三第4次月考理科数学试题命题:张耀华 审题:高三数学备课组一.选择题:本大题共8小题,每小题5分,共40分.在每小题给出的四个选项中,只有一项是符合要求的.1.设1,0()001,0x f x x x >⎧⎪==⎨⎪-<⎩,,1,()0,x g x x ⎧=⎨⎩为有理数为无理数,则[()]f g π的值为( )A .1B .0C .1-D .π2.已知全集R U =,集合2{|30}A x x x =->,{|1}B x x =>,则()U x A B ∈ ð是()x A B ∈ 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3.如图,⊙O :222π=+y x 内的正弦曲弦x y sin =与x 轴围成的区域记为M (图中阴影部分)随机往⊙O 内投一个点A ,则点A 落在区域M 内的概率是 ( )A .24πB .22πC .34π D .32π4.一个空间几何体的主视图是长为4,宽为3的长方形,左视图是边长为2的等边三角形,俯视图如图所示,则这个几何体的体积为( ) A .332 B .32C .334 D .34 5.已知命题p :R x ∈∃,012≤+mx ,命题R x q ∈∀:,012>++mx x ,若q p ∨为假命题, 则实数m 的取值范围为 ( )A .2-≤m 或2≥mB .2-≤mC .2≥mD .22≤≤-m 6.若函数21m y x x n n =-+的图象在点1(0,)M n处的切线l 与圆22:1C x y +=相交,则点(,)P m n 与圆C 的位置关系是( )A .圆内B .圆外C .圆上D .不确定俯视图7.设等差数列{}n a 的前n 项和为n S ,已知()()3771201211a a -+-=,()()3200620061201211a a -+-=-,则下列结论正确的是 ( )A .20122012S =-,20127a a >B .20122012S =,20127a a >C .20122012S =-,20127a a <D .20122012S =,20127a a <8.已知)(x f 为定义在),(+∞-∞上的可导函数,且)()(x f x f '<对于R x ∈恒成立,且e 为自然对数的底,则( )A .2012(1)(0),(2012)(0)f e f f e f >⋅>⋅ B .2012(1)(0),(2012)(0)f e f f e f <⋅>⋅ C .2012(1)(0),(2012)(0)f e f f ef >⋅<⋅ D .2012(1)(0),(2012)(0)f e f f e f <⋅<⋅二.填空题:本大题共7小题,每小题5分,共35分.请将答案填在答题卷上.9.若复数2()12bib R i-∈+的实部与虚部互为相反数,则b = .10.已知tan 2x =,则221sin sin cos cos 2x x x x -⋅+=________________.11.已知函数)0,)(4sin()(>∈+=w R x wx x f π的最小正周期为π,将)(x f y =的图像向左平移(0)2πϕϕ<<个单位长度,所得图像关于y 轴对称,则ϕ= .12.在计算“1223(1)n n ⨯+⨯+⋅⋅⋅++”时,某同学学到了如下一种方法,先改写第k 项:1(1)[(1)(2)(1)(1)]3k k k k k k k k +=++--+, 由此得:112(123012)3123(234123)31(1)[(1)(2)(1)(1)]3n n n n n n n n ⎧⨯=⨯⨯-⨯⨯⎪⎪⎪⨯=⨯⨯-⨯⨯⎨⎪⎪+=++--+⎪⎩,上述n 个等式两边分别相加, 得:11223(1)(1)(2).3n n n n n ⨯+⨯+⋅⋅⋅++=++ 类比上述方法,请你计算“123234(1)(2)n n n ⨯⨯+⨯⨯+⋅⋅⋅+++”,其结果是 .13.已知b a ,均为正数,且3=+b a ,则b a +++11的最大值为 .14.已知平面向量,()αβαβ≠ 满足2α= ,且α 与βα- 的夹角为120°,则(1)t t αβ-+ (t R ∈)的最小值是___ _.15.在平面直角坐标系中,定义1212(,)d P Q x x y y =-+-为两点11(,)P x y ,22(,)Q x y 之间的“折线距离”.则坐标原点O与直线20x y +-=上的点A 的“折线距离“是 ; 圆221x y +=上一点与直线20x y +-=上一点的“折线距离”的最小值是 .三.解答题:本大题共6小题,共75分.解答应写出文字说明,证明过程或演算步骤. 16.(本小题满分12分)如图,当甲船位于A 处时获悉,在其正东方向相距20海里的B 处有一艘渔船遇险等待营救.甲船立即前往救援,同时把消息告知在甲船的南偏西30 ,相距10海里C 处的乙船. (1)求处于C 处的乙船和遇险渔船间的距离;(2)设乙船沿直线CB 方向前往B 处救援,其方向与成θ角,求()x x x f cos cos 43sin sin 22θθ+=()R x ∈的值域.17.(本小题满分12分)如图,AC 是圆O 的直径,点B 在圆O 上,030BAC ∠=,BM AC ⊥交AC 于点M ,EA ⊥平面ABC ,FC //EA ,4AC =,3EA =,1FC =. (1)证明:EM BF ⊥;(2)求平面BEF 与平面ABC 所成锐二面角的余弦值.18.(本小题满分12分) 已知曲线)0(1)1(log )(2>++=x x x x f 上有一点列*(,)()n n n P x y n N ∈,点n P 在x 轴上的射影是)0,(n n x Q ,且*121(,2)n n x x n N n -=+∈≥,11=x .(1)求数列}{n x 的通项公式n x ;(2)设四边形11++n n n n P Q Q P 的面积是n S ,求证:4121121<+++nnS S S .C19.(本小题满分13分)某企业科研课题组计划投资研发一种新产品,根据分析和预测,能获得10万元~1000万元的投资收益.企业拟制定方案对课题组进行奖励,奖励方案为:奖金y (单位:万元)随投资收益x (单位:万元)的增加而增加,且奖金不超过9万元,同时奖金也不超过投资收益的20%.现该企业计划用一个函数()y f x =来模拟这一奖励方案. (1)试写出模拟函数()y f x =所要满足的条件;(2)试分析函数模型4lg 3y x =⋅-是否符合奖励方案的要求?并说明你的理由.20.(本小题满分13分)设函数2()()ln ()f x x a x a R =-∈.(1)若x e =为()y f x =的极值点,试求实数a 的值;(2)求实数a 的取值范围,使得对任意(0,3]x e ∈恒有2()4f x e ≤成立.注:e 为自然对数的底数.21.(本小题满分13分)设双曲线C :2212x y -=的左、右顶点分别为A 1、A 2,垂直于x 轴的直线m 与双曲线C 交于不同的两点P 、Q .(1)若直线m 与x 轴正半轴的交点为T ,且121A P A Q ⋅=,试求点T 的坐标;(2)求直线1A P 与直线2A Q 的交点M 的轨迹E 的方程;(3) 过点F (1,0)作直线l 与(2)中的轨迹E 交于不同的两点A 、B ,设FA =λ·FB,若[2,1]λ∈--,求|TA +TB|(T 为(1)中的点)的取值范围.。
株洲市二中2013届高三考前演练理科数学试题(5月27-28日)命题、审题:高三数学备课组时量:120分钟分值:150分第Ⅰ卷(共40分)一.选择题(本大题共8小题,每小题5分,共40分.在每小题给出的四个选项中,只有一项是符合要求的.)1.若集合{|01}A x x=≤<,2{|2}B x x x=<,则A B=( A )A.{|01}x x<< B. {|01}x x≤< C. {|01}x x<≤ D. {|01}x x≤≤2.若复数z满足:1(1)z z i+=-,则复数z=( B )A. iB. i-C.1i-D.1i+3.若一个四面体的四个面均为直角三角形,正视图与俯视图如图所示,均为直角边为1的等腰直角三角形,则该几何体的侧视图的面积为(C )A.14B C.12D.24.若ABC∆的三个内角满足sin:sin:sin5:11:13A B C=,则ABC∆( C )A. 一定是锐角三角形B. 一定是直角三角形C. 一定是钝角三角形D. 可能是锐角三角形,也可能是钝角三角形5.按右面的程序框图运行后,输出的S应为(BA.B.3C D.46.函数()()220,2cos02x xf xx xπ+-≤⎧⎪=⎨⎛⎫≤≤⎪⎪⎝⎭⎩<的图象与x轴所围成的封闭图形的面积为( D )A.32B.52C. 3D. 47.设1F,2F分别为双曲线22221(0,0)x ya ba b-=>>的左、右焦点,若在双曲线右支上存在一点P,满足212||||PF F F=,且2F到直线1PF的距离等于双曲线的实轴长,则该双曲线的离心率为( B )A.34B.35C.45D.441正视图8.已知函数2,01,()12, 1.2x x x f x x +<⎧⎪=⎨+⎪⎩≤≥若0a b >≥,且()()f a f b =,则()bf a 的取值范围是( A )A. 5[,3)4B. 5[,3)2C. 1[,3)2D. [1,3)第Ⅱ卷 (共110分)二.填空题(本大题共8个小题,考生作答7个小题,每小题5分,共35分.把答案填在答题卡中对应题号后的横线上.)(一)选做题:请考生在第9、10、11三个小题中任选2题作答,如果全做,则按前2题给分. 9.(选修4—1:几何证明选讲) 以Rt ABC ∆的直角边AB 为直径的圆O 交AC 边于点E ,点D 在BC 上,且DE 与圆O 相切.若056A ∠=,则BDE ∠ 068 .10.(选修4—4:坐标系与参数方程) 在极坐标系中,已知点)4A π,曲线2sin 4cos ρθθ=的焦点为F ,则||AF = 5 . 11.(选修4—5:不等式选讲)若正数a ,b 满足a +b =1,则13a +2+43b +2的最小值为 7 .(二)必做题:第12——16题12.在△ABC 中,已知AB =2,∠ABC =60°,AD ⊥BC ,D 为垂足,则AD AC ⋅=3 .13.采用系统抽样方法从960人中抽取32人做问卷调查,为此将他们随机编号为1,2, …,960,分组后在第一组采用简单随机抽样的方法抽到的号码为9. 抽到的32人中,编号落入区间[]1,450的人做问卷A ,编号落入区间[]451,750的人做问卷B ,其余的人做问卷C . 则抽到的人中,做问卷B 的人数为 10 .14.已知函数3()f x x x =+,对任意的[2,2]m ∈-,(2)()0f mx f x -+<恒成立,则实数x 的取值范围是 2(2,)3- .15.将一颗骰子连续抛掷三次,它落地时向上的点数依次构成等比数列的概率与构成等差数列的概率之比为 9.16.已知函数2()4sin sin ()cos 242xf x x x π=⋅++. (1)设0ω>为常数,若()y f x ω=在区间2[,]23ππ-上是增函数,则ω的取值范围 是 3(0,]4;EDC B A(2)若|()|2f x m -<成立的充分条件是263x ππ≤≤,则实数m 的取值范围是(1,4).三、解答题(本大题共6小题,共75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)某校设计了一个实验考查方案:考生从6道备选题中一次性随机抽取3道题,按照题目 要求独立完成全部实验操作.规定:至少正确完成其中2道题的便可通过.已知6道备选 题中考生甲有4道题能正确完成,2道题不能完成;考生乙每题正确完成的概率都是23,且每题正确完成与否互不影响. (1)求甲、乙两考生正确完成题数的概率分布列,并计算其数学期望; (2)请分析比较甲、乙两考生的实验操作能力. 解:(1)设甲、乙正确完成实验操作的题数分别为ξ,η,则ξ取值分别为3,2,1;η取值分别为3,2,1,0.51)1(362214===ξC C C P ,53)2(361224===ξC C C P ,51)3(360234===ξC C C P . ∴考生甲正确完成题数的概率分布列为2513532511=⨯+⨯+⨯=ξE .…………………………3分∵==)0(ηP 271)321(303=-C , 同理:276)1(==ηP ,2712)2(==ηP ,278)3(==ηP . ∴考生乙正确完成题数的概率分布列为:227832712227612710=⨯+⨯+⨯+⨯=ηE .………………7分 (2)∵5251)32(53)22(51)12(222=⨯-+⨯-+⨯-=ξD , 32278)32(2712)22(276)12(271)02(2222=⨯-+⨯-+⨯-+⨯-=ηD . (或32==npq D η). ∴η<ξD D . ∵8.05153)2(=+=≥ξP ,74.02782712)2(≈+=≥ηP , ∴)2()2(≥η>≥ξP P .……………10分从做对题数的数学期望考察,两人水平相当; 从做对题数的方差考察,甲较稳定;从至少完成2道题的概率考察,甲获得通过的可能性大. 因此可以判断甲的实验操作能力较强.……………………12分18.(本小题满分12分)在数列{}n a 中,123a =,且对任意的n N *∈都有121n n n a a a +=+. (1)求证:1{1}na -是等比数列; (2)若对任意的n N *∈都有1n n a pa +<,求实数p 的取值范围.解:(1) 由121n n n a a a +=+,得11111111(1)222n n n n n na a a a a a ++--=-==-. 又由123a =,得111102a -=≠. 因此,1{1}n a -是以11112a -=为首项,以12为公比的等比数列.………5分(2)由(1)可得:111111()222n n n a --=⨯=即 221n n n a =+, 111221n n n a +++=+,于是所求的问题:“对任意的n N +∈都有1n n a pa +<成立”可以等价于问题:“对任意的*N n ∈都有11111122122112122121n n n n n n n n n a p a ++++++++>=⋅==++++成立”.若记11()121n f n +=++,则()f n 显然是单调递减的,故1116()(1)1215f n f +≤=+=+. 所以,实数p 的取值范围为65p >.………………………12分19.(本小题满分12分)如图,在四棱锥P -ABCD 中,底面ABCD 为直角梯形, AD ∥BC ,90oBAD ∠=,PB ⊥平面ABCD ,CD ⊥BD , PB =AB =AD =1,点E 在线段PA 上,且PE =2EA . (1)求证:PC ∥平面BDE ;(2)求二面角E -BD -A 的余弦值. 解:(1)法一:连AC ,交BD 于F ,连EF ,设法证明:12AE AF EP FC ==, 从而:EF ∥PC 故PC ∥平面BDE 法二:建立空间直角坐标系B-xyz ,如图, 求出点A 、D 、C 、E 、P 的坐标,再求出平面EBD 的法向量111(,,1)22n =- ,计算:10n PC ⋅=从而得到:PC ∥平面BDE(2)在空间直角坐标系中,由(1)得:平面EBD 的法向量1(,,1)22n =-又平面ABD 的法向量2(0,0,1)n =所以 121212cos ,3||||n n n n n n ⋅<>==⋅P BCE故二面角E -BD -A20.(本小题满分13分)某单位设计一个展览沙盘,现欲在沙盘平面内,布设一个对角线在l 上的四边形电气 线路,如图所示. 为充分利用现有材料,边BC 、CD 用一根5米长的材料弯折而成; 边BA 、AD 用一根9米长的材料弯折而成. 要求A ∠和C ∠互补,且AB BC =. (1)设AB x =米,cos ()A f x =,求()f x 的解析式,并指出x 的取值范围; (2)求四边形ABCD 面积的最大值. 解:(1)ABD ∆中,由余弦定理:222222cos (9)2(9)cos BD AB AD AB AD Ax x x x A=+-⋅=+---又CBD ∆中,由余弦定理:222222cos (5)2(5)cos BD BC CD BC CD Cx x x x C=+-⋅=+---而A ∠和C ∠互补,∴cos cos A C =-∴2222(9)2(9)cos (5)2(5)cos x x x x A x x x x C +---=+---⇒ 2cos A x= 由 2cos 1A x=<,∴25x << 故2cos A x=(25)x << (2)11sin sin 22ABD ABCD BCD S S S AB AD A CB CD C ∆∆=+=⋅⋅+⋅⋅ 1[(9)sin (5)]2x x A x x sinC =⋅-+⋅- ∵ A ∠和C ∠互补,∴sin A sinC =∴((7)sin (7ABCD S x x A x x =-=-=设 22(7)(4)y x x =-- 25x <<则 2(7)(4)(21)y x x x '=--+∴ 当24x <<时,0y '>,y ;当45x <<时,0y '<,y ∴ 当4x =时,max 108y =DCBAl故当4x =时,2max ()S m ==21.(本小题满分13分)如图,在平面直角坐标系xOy 中,已知椭圆E :22221(0)x y a b a b +=>>的离心率e =,12,A A 分别是椭圆E 的左、右两个顶点,圆2A 的半径为a ,过点1A 作圆2A 的切线,切点为P ,在x 轴的上方交椭圆E 于点Q . (1)求直线OP 的方程; (2)求1PQQA 的值; (3)设a 为常数.过点O 作两条互相垂直的直线,分别交椭圆E 于点,B C ,分别交圆2A 于点,M N ,记O B C △和OMN △的面积分别为1S 、2S ,求12S S ⋅的最大值.解:⑴连结2A P ,则21A P A P ⊥,且2A P a =,又122A A a =,所以1260A A P ∠=.所以260POA ∠= ,所以直线OP的方程为y .…………………………3分 ⑵ 由⑴知,直线2A P的方程为)y x a =-,1A P的方程为)y x a +, 联立解得2P a x =.因为e =c a =2234c a =,2214b a =,故椭圆E 的方程为222241x y a a =+.由2222),41,y x a x y a a ⎧=+⎪⎪⎨⎪=⎪⎩+解得7Q a x =-,所以1()3274()7a a PQ a QA a --==---. ………………………………………………8分 ⑶ 不妨设OM 的方程为(0)y kx k =>,联立方程组2222,41,y kx x y aa =⎧⎪⎨=⎪⎩+解得B,所以OB = 用1k-代替上面的k,得OC =.同理可得,OM =,ON =.所以41214S S OB OC OM ON a ⋅=⋅⋅⋅⋅=.15=≤,当且仅当1k =时等号成立,所以12S S ⋅的最大值为45a . ……………………13分22. (本小题满分13分)已知函数3()ln ,()2af x xg x x==-(a 为实数). (1)当a =1时,求函数()()()x f x g x ϕ=-在[4,)x ∈+∞上的最小值;(2)若方程2()()f x e g x =(其中e 为自然对数的底)在区间1,12⎡⎤⎢⎥⎣⎦上有解,求实数a 的取值范围;(3)证明:[]1512(21)()(1)21460nk n f k f k f k n =+<+--+<+∑,n N *∈.解:(1)当1a =时,13()()()ln 2x f x g x x x ϕ=-=+-,则'22111()x x x x xϕ-=-=∵在区间(0,1]上,'()0x ϕ≤,在区间[1,+∞)上,'()0x ϕ≥∴()x ϕ在区间(0,1]上单调递减,在区间[1,+∞)上单调递增∴在x ∈[4,+∞)上,()x ϕ的最小值为5(4)ln 44ϕ=-. ………3分 (2)∵方程2()()f x e g x =在区间1,12⎡⎤⎢⎥⎣⎦上有解即2ln 32xa ex =-在区间1,12⎡⎤⎢⎥⎣⎦上有解即332a x x =-在区间1,12⎡⎤⎢⎥⎣⎦ 上有解 令33()2h x x x =-,x ∈1,12⎡⎤⎢⎥⎣⎦∴'23()32h x x =- ∵在区间1,22⎡⎢⎣⎦ 上,'()0h x ≥,在区间,12⎤⎥⎣⎦上,'()0h x ≤ ∴()h x在区间12⎡⎢⎣⎦上单调递增,在区间⎤⎥⎣⎦上单调递减, 又115(1),()228h h ==∴(1)()(2h h x h ≤≤即1()22h x ≤≤故1,22a ⎡∈⎢⎣⎦……………8分(3)设2(21)()(1)k a f k f k f k =+--+由(1)知,()x ϕ的最小值为(4)ln 404ϕ=-> ∴31ln 2x x>-(x≥4) 又∵24414(1)k k k k ++>+22223(1)31441124412444151151144(21)44(21)(23)k k k k k a k k k k k k k +++-∴>-=-++++=+>++++5111()482123k k =+-++ ∴151111111( (4835572123)kk a n n n =>+-+-++-++∑ 5111511151()()n n n =+-≥+-=+ 244111ln 42(1)1k k k a k k k k ++=<+--++,即1112+-+<k k a k 1121211nkk a n n n =<+-<++∑ 故[]1512(21)()(1)21460nk n f k f k f k n =+<+--+<+∑, n ∈N*. …………13分。