湖南省株洲市芦淞区2018-2019年九年级上学期期末考试
湖南省株洲市九年级上学期期末数学试卷

湖南省株洲市九年级上学期期末数学试卷姓名:________ 班级:________ 成绩:________一、选择题 (共12题;共24分)1. (2分)在 -1,0,-2,这四个数中,最小的数是()A . -1B . 0C . -2D .2. (2分)(2019·自贡) 下列图案中,既是轴对称图形又是中心对称图形的是()A .B .C .D .3. (2分) (2019八下·武昌月考) 下列计算正确的是()A .B .C .D .4. (2分)(2016·荆州) 下列运算正确的是()A . m6÷m2=m3B . 3m2﹣2m2=m2C . (3m2)3=9m6D . m•2m2=m25. (2分) (2017八下·栾城期末) 下列调查方式中,适合用普查方式的是()A . 要了解一批等灯泡的使用寿命B . 要了解栾城电视台“栾城新闻”的收视率C . 要了解某校篮球队12名队员的身高状况D . 要了解全国人民对“春节连欢晚会”的满意度6. (2分) (2017八上·揭西期末) 如图,已知AB∥CD,DE⊥AC,垂足为E,∠A=120°,则∠D的度数为()A . 30°B . 60°C . 50°D . 40°7. (2分) (2019八下·余杭期中) 一组数据1,2,3,4,4,10.去掉10,剩下的数据原数据相比,不变的是()A . 平均数B . 中位数C . 众数D . 平均数和众数8. (2分)已知一元二次方程 -4x +3=0两根为x1、x2 ,则x1•x2=()A . 4B . 3C . -4D . -39. (2分)(2018·井研模拟) 如图,四边形ABCD内接于⊙O,延长CO交圆于点E,连接BE.若∠A=100°,∠E=60°,则∠OCD的度数为()A . 30°B . 50°C . 60°D . 80°10. (2分)已知P(x1 , 1),Q(x2 , 2)是一个函数图象上的两个点,其中x1<x2<0,则这个函数图象可能是()A .B .C .D .11. (2分) (2017七上·港南期中) 观察图中正方形四个顶点所标的数字规律,可知数2016应标在()A . 第503个正方形的左下角B . 第503个正方形的右下角C . 第504个正方形的左下角D . 第504个正方形的右上角12. (2分)(2017·广陵模拟) 如图,点A(1,2)在反比例函数y= (x>0)上,B为反比例函数图象上一点,不与A重合,当以OB为直径的圆经过A点,点B的坐标为()A . (2,1)B . (3,)C . (4,0.5)D . (5,0.4)二、填空题 (共6题;共6分)13. (1分) (2019九上·舟山期中) 某市常住人口约为7680000人,数据“7680000”用科学记数法可表示为________.14. (1分)计算: +(﹣1)0+(﹣1)22=________.15. (1分)若两个三角形相似,其中一个三角形的两个角分别为60°、50°,则另一个三角形的最小的内角为________度.16. (1分)(2017·磴口模拟) 如图,点P是等边三角形ABC内的一点,若将△PA B绕点A逆时针旋转到△P′AC,则∠PAP′的度数为________.17. (1分) (2017九上·北京期中) “双十二”期间,小冉的妈妈在网上商城给小冉买了一个书包,除了书包打八折外还随机赠送购买者1支笔(除颜色外其它都相同且数量有限).小冉的妈妈购买成功时,还有5支黑色,3支绿色,2支红色的笔.那么随机赠送的笔为绿色的概率为________.18. (1分)(2017·西华模拟) 如图,Rt△ABC中,∠B=90°,AB=6,BC=8,将Rt△ABC绕点C按顺时针方向旋转90°,得到Rt△A′B′C,则边AB扫过的面积(图中阴影部分)是________.三、解答题 (共8题;共85分)19. (10分) (2020七下·镇平月考) 解下列方程组:(1)(2)20. (5分)如图,已知△ABC和△DAE,D是AC上一点,AD=AB,DE∥AB,DE=AC.AE与BC相等吗?为什么?21. (10分)化简下列各式:(1)(x﹣1)2(x+1)2﹣1;(2)÷(﹣x+2)+ .22. (10分)(2014·北海) 经过某十字路口的汽车,它可能继续直行,也可能向左转或向右转,这三种可能性大小相同,现在两辆汽车经过这个十字路口.(1)请用“树形图”或“列表法”列举出这两辆汽车行驶方向所有可能的结果;(2)求这两辆汽车都向左转的概率.23. (10分)如图,大楼AN上悬挂一条幅AB,小颖在坡面D处测得条幅顶部A的仰角为30°,沿坡面向下走到坡脚E处,然后向大楼方向继续行走10米来到C处,测得条幅的底部B的仰角为45°,此时小颖距大楼底端N处20米.已知坡面DE=20米,山坡的坡度i=1:(即tan∠DEM=1:),且D、M、E、C、N、B、A在同一平面内,E、C、N在同一条直线上.(1)求D点距水平面EN的高度?(保留根号)(2)求条幅AB的长度?(结果精确到1米)(参考数据:≈1.73,≈1.41)24. (10分)(2016·杭州) 已知函数y1=ax2+bx,y2=ax+b(ab≠0).在同一平面直角坐标系中.(1)若函数y1的图象过点(﹣1,0),函数y2的图象过点(1,2),求a,b的值.(2)若函数y2的图象经过y1的顶点.①求证:2a+b=0;②当1<x<时,比较y1,y2的大小.25. (15分)(2014·宿迁) 如图,已知△BAD和△BCE均为等腰直角三角形,∠BAD=∠BCE=90°,点M为DE 的中点,过点E与AD平行的直线交射线AM于点N.(1)当A,B,C三点在同一直线上时(如图1),求证:M为AN的中点;(2)将图1中的△BCE绕点B旋转,当A,B,E三点在同一直线上时(如图2),求证:△ACN为等腰直角三角形;(3)将图1中△BCE绕点B旋转到图3位置时,(2)中的结论是否仍成立?若成立,试证明之,若不成立,请说明理由.26. (15分)如图,二次函数y=ax2+bx﹣3的图象与x轴交于A(﹣1,0),B(3,0)两点,与y轴交于点C.该抛物线的顶点为M.(1)求该抛物线的解析式;(2)判断△BCM的形状,并说明理由;(3)探究坐标轴上是否存在点P,使得以点P、A、C为顶点的三角形与△BCM相似?若存在,请直接写出点P的坐标;若不存在,请说明理由.参考答案一、选择题 (共12题;共24分)1-1、2-1、3-1、4-1、5-1、6-1、7-1、8-1、9-1、10-1、11-1、12-1、二、填空题 (共6题;共6分)13-1、14-1、15-1、16-1、17-1、18-1、三、解答题 (共8题;共85分)19-1、19-2、20-1、21-1、21-2、22-1、22-2、23-1、23-2、24-1、24-2、25-1、25-2、25-3、26-1、26-2、。
株洲九年级期末考试卷数学

株洲九年级期末考试卷数学一、选择题(每题3分,共30分)1. 下列哪个选项是最小的正整数?A. 0B. 1C. -1D. 22. 如果a,b是实数,且a > b,那么下列哪个不等式是正确的?A. a + 1 > b + 1B. a - 1 > b - 1C. a × 1 > b × 1D. a ÷ 1 > b ÷ 13. 一个圆的半径是5,那么它的面积是多少?A. 25πB. 50πC. 75πD. 100π4. 一个二次方程x² + 4x + 4 = 0的解是:A. x = -2B. x = 2C. x = 1D. x = -15. 以下哪个是等差数列1, 3, 5, 7, ...的第10项?A. 19B. 21C. 23D. 256. 一个直角三角形的两条直角边分别是3和4,斜边的长度是:A. 5B. 6C. 7D. 87. 一个正方体的体积是64立方厘米,它的边长是:A. 4厘米B. 6厘米C. 8厘米D. 10厘米8. 一个数的平方根是4,这个数是:A. 16B. -16C. 8D. -89. 函数y = 2x + 3在x = 1处的值是:A. 5B. 6C. 7D. 810. 以下哪个是函数y = x² - 4x + 4的顶点坐标?A. (2, -4)B. (2, 0)C. (-2, 0)D. (0, 4)二、填空题(每题2分,共20分)11. 一个数的立方根是2,这个数是______。
12. 一个等差数列的首项是2,公差是3,第5项是______。
13. 一个直角三角形的斜边长是13,一条直角边长是5,另一条直角边长是______。
14. 一个圆的直径是14,它的周长是______。
15. 一个二次方程x² - 5x + 6 = 0的根是______和______。
16. 函数y = 3x - 2与x轴的交点坐标是______。
湖南省株洲市九年级(上)期末英语试卷含答案

九年级(上)期末英语试卷题号I II III IV V VI总分得分一、单项选择题(本大题共10 小题,共 10.0 分)1. Cindy ___ speak English very well . She has lived in London for many years .()A. mustB. can'tC. could2.Many of the kids ___not to play on the streets after the large traffic accidents happened.()A. toldB. are toldC. were told.3.Chinese moms always help their kids _______any problems , which makes the kids getused to ________ their parents.()A. deal with,depend onB.C. deal with,depending on4.---Could you tell me ________ ?---Next month .()A. when he came backB.C. when will he come back keep away from , depend on when he will come back5. When we grow up , we often regret __________ our parents .()A. to look up toB. being proud ofC. talking back to6. -My teacher always tells us ___________ knowledge is! ()A. what an importantB. how importantC. that important7.--I believe Carmen will catch up with us .-- I think so . _________ she loses herself in computer games.()A. UnlessB. IfC. Because8.As she gets older, she dares ___ questions in class , and she can speak_____ than before.()A. to answer,aloudB. to answer,louderC. answering,more loudly9. I like the cartoon _____ has a happy ending and makes me _____ .()A. which,to laughB. that,laughC. who,laugh10.--Could you keep an eye on my luggage when I am away .---____ ()A. That's all right.B. Come onC. With pleasure二、完形填空(本大题共10 小题,共15.0 分)Tom brought a box of biscuits to the summer camp . He ate a few and placed the rest under his bed. After lunch , he found the box was gone . He went to tell his camp (11)aboutit . The next day, the coach saw a boy hiding and eating Tom's biscuits (12)a largedesk . He came up with an idea to(13)the problem . He found Tom and said to him , "I know who took away your biscuits . Will you help me to teach him a lesson ? ""Well , yes are you going to punish (14), sir? " Tom asked. "No , I am not," the coach explained(15)"That would only make him(16)you . I want you to write to your mother and ask for more biscuits . "Tom received another box of biscuits by mail from (17) a few days later . "Now , " said the coach, "go and share them with the boy who (18)your biscuits . " Tom didn't understand the coach's intention(19)he still followed his advice .Half an hour later the coach saw the two boys come up the hill , arm in arm. The boy was trying to ask Tom to accept his toy robot in payment for the stolen biscuits . And Tom was refusing the gift from his new friend . He said that the few biscuits were not so(20) In some situations , forgiveness is better than punishment .11. A. doctor B. cook C. coach12. A. at B. on C. under13. A. study B. research C. deal with14. A. me B. him C. her15. A. patiently B. angrily C. sadly16. A. thank B. love C. hate17. A. his coach B. his mother C. the boy18. A. stole B. gave C. bought19. A. but B. since C. though20. A. different B. valuable C. cheap三、阅读理解(本大题共19 小题,共40.0 分)AIt' s a Mailbon It'sa bird houseNo.Wait .It's a Library!Sunshine park has A little free library !The way it works is simple:We bring to the lbrary a number of good books that we hope will interestour neighbors.You stop by and take whatever catches your eyes.You retum and bring other books for the library whenever you can.Books are always a gift. Never for sale!Join us for our small opening at 9 am on Feb 25 th, 2019.Call 9051 6601 or email bryan beautiful-gathering.com for more information!21. What is TRUE according to the advertisement (广告)?______A. This is an advertisement for a Mailbox.B. People should pay for the books you like to read in the library.C. The library will open in February.22.Where are the books in the library from ? ______A.They are bought from the bookstore .B.They are from the Bird House .C.People give the books to the library .BYVE Hotel Miami146 Biscayne Bld. Miami★★★Last booking: 1hour ago14 others viewing this property now23.7 out of 5 ( 15 reviews)Located in the city's financial and business center, 2 blocks from Port of Miami , across from Bayside Marketplace , Bayfront Park , Flagler Street shopping , andReview from Betty :"Nice place , clean and great services. Check in and out was fast .Location is extremely great! Closed to everything and very convenient for our little getaway trip . They also gave us teo welcoming drink vouchers! That was a nice gesturer !"For more information , click on the linkwww . Travelocity . come ( 1) Where is YVE Hotel Miami?______A. Next to Port of Miami.B. Across from Bayside Marketplace.C. Far away from the business center.(2)What does Betty think of the hotel?______A. It is too far from the shopping center . B . The food service is very fast . C. It is convenient.24. If you want to know more about the hotel , what should you do ? ______A. Surf the Internet.B. Book a room.C. Read the review from Betty.CWhen someone talks about the brands of the smartphones in the world, which brand will you think of ? Most people will think about Apple . But now in China and even in the world ,Huawei is a wonder . Although it started producing mobile phones not many years ago , it has become one of the most famous phone companies.Now Huawei has got third place at the mobile market , just following Apple andSamsung. After seeing more of its smartphones were sold last year , Huawei appears to be more confident in its bigger goals ."We hope that in three years our market share can be the top two and in five years our market share can be the top one, " Richard Yu , CEO of Huawei's Consumer (花费者) Business Group , said in a recent TV interview .The company sold 108 million smartphones in 2015 , compared with 2014 , the number increased by 44 percent, though it was much smaller than Apple's 231.5 million iPhones and Samsung's 317.2 million smartphones ."The number of our smartphones is still growing , " Yu said , "and our company is expecting an increase of 30% in smartphone shipments (出货量). It'll be a great success. " Although Huawei's smartphones sold well in Western Europe and China , the market in the US is another example. Yu said that the company was "so late" to the US . However , we are trying hard to raise our market share there in the next few years .25. According to the passage, which are top two biggest smartphone companies now ?______A. Samsung and AppleB. Samsung and HuaweiC. Apple andHuawei26. What does the underlined word "share" in paragraph 3 mean in Chinese ? ______A. 分享B. 股票C. 份额27. How many smartphones were sold by Huawei in 2015 ? ______A. 108 millionB. 231.5 millionC. 317.2 million28. Which of the following is TRUE according to the passage ?______A.Huawei has become the best at the mobile market .B.Huawei's market share will be the top one in five years .C. Huawei is trying hard to make its market share rise in America.29. What does the passage mainly want to tell us ? ______A.Smartphones are getting popular around the world .B.Huawei's phone company is getting better and better .C.Huawei is trying hard to make money .DYour brain controls everything you do . It makes it possible for you tothink ,learn,create and feel;to blink(眨眼) and breathe-thisfantastic control center is your brain . It is so amazing that a famousscientist once called it "the most complex (复杂) thing we have yetdiscovered in our universe" .Can this small grey organ (器官),which weighs less than one and ahalf kilos , really do so much ? Amazingly , your brain contains about 100 billion neurons (神经元) -it would take you over 3,000 years to count them all.Believe it or not,the activity in your brain never stops . Your neurons create and send more messages than all the phones in the world . And although one neuron creates only a little electricity , all your neurons together can produce enough electricity to power a light bulb (灯泡).So exactly how fast does your brain work ? Well , imagine this : a bee lands on yourfoot . Neurons in your skin send this information to your brain at a speed of more than 240 kilometers per hour . Your brain then uses other neurons to send the message back to your foot to shake the bee off quickly . These neurons can send this information at more than 320 kilometers per hour . No computer has your brain's unbelievable ability to deal with theamount of information coming from your eyes,ears and other sensory organs.But how does your brain allow you to learn things that you will use in the future?The structure of your brain changes every time you have a new thought , remember or learn something . For example, riding a bike seems impossible at first , but soon you are able to do it . How ? As you practice , your brain sends "bike riding" messages again and again. Soon, the actions are learnt and you are able to ride a bike easily from then on . 30. What can we know about neurons from the passage ? ______A. receive messages very slowlyB. are only found in your skinC. send messages to your brain31.In Paragraph 3, why does the writer mention computers ? ______A.tell us how fast our brains work .B.show how fast they have becomeC.say that computers have no use.32. What will your brain do when you have a new thought?______A.you remember somethingB.the structure of your brain changesC.your brain will power a light bulb33.Which of the statements about the brain is TRUE ? ______A. The electricity produced by the neurons can hardly power a light bulb.B. We learn a new skill by sending the messages again and again through the brain.C. After receiving the information,the brain send the same neurons back to your foot.34. What is the article mainly about?______A.all the steps when your brain learns things .B.how the brain makes people smarter than computers .C.what an unbelievable organ the human brain is .EMark Zuckerberg , is an American computer programmer , CEO, and founder(首创人)of Facebook. His net worth is about US $ 58.6 billion , ranking him the fifth richest personin the world . On December 1st , 2015, he and his wife announced that they would give away 99 percent of their Facebook shares to the Chan Zuckerberg Fund(基金). Since 2010,many people think Zuckerberg is one of the wealthiest and most influential people in the world.Born in 1984 ,he and his three sisters were brought up in a small village in New York ,at High School ,Zuckerberg was outstanding in classes.He won prizes in science( math ,astronomy , and physics). He could also read and write French, Hebrew , Latin , and ancient Greek besides English when he was at school. He began using computers and writing software in the middle school .In 2004 ,Zuckerberg launched(倡始)Facebook from Harvard .He left Harvard in his second year to complete his project-facebook . Helped by his college roommates and fellow Harvard students, facebook became popular rapidly , reaching one billion users by 2012 .In 2003 , Zuckerberg met Priscilla Chan , at a party during his second year at Harvard . In2010 , they got married and had their first baby . The couple announced on their Chinese New Year video , that their daughter's Chinese name is Chen Mingyu . On Mar 18 th , 2016 ,while visiting Beijing , He posted on facebook, "It's great to be back in Beijing! I started my visit with a run through Tiananmen Square , past the Forbidden City and over to the Temple of Heaven." With a Chinese American wife and speech in Mandarin (一般话) in Tsinghua University , Zuckerberg is famous in China .Last year, Zuckerberg finally succeeded in getting the degree from Harvard University.35. How many languages could Zuckerberg read and write when he was at school ? ______A.3B.4C.536.What do many people think of Zuckerberg ? ______A.He has a lot of influence in the world .B.He is the smartest. B . He is hard-working .37. Which place did NOT Zuckerberg run past to begin his visit in China?______A. Tsinghua UniversityB. the Temple of HeavenC. Tiananmen Square38.What can we know from the first paragraph ? ______A.Zuckerberg made a lot of money by selling his shares .B.Facebook is the biggest company at that time .C.Zuckerberg becomes very successful now .39. Which of the following is TRUE?______A.Zuckerberg can't speak any Chinese.B.Zuckerberg received little popularity from usersC.Zuckerberg and his wife graduated from Harvard .四、任务型阅读 -简答(本大题共 1 小题,共 10.0 分)40.There is a large problem for the restaurants . Many children make so much noise in therestaurants, which makes other customers uncomfortable . How to solve theproblem ? Last month some parents visited a pizza restaurant in Florida with theirchildren . On the door, they saw a sign "NO CHILDREN . " "Why can't we bring ourchildren ?" "What on earth does the owner want to do ? " The parents were surprisedand complained angrily . So why did the restaurant put up the sign on its door ?Troy Taylor , the owner of the pizza restaurant, found that many parents couldn't control their children and many children couldn't have meals quietly , so they disturbed(打搅)other customers. So he made up his mind to ban (严禁) children from hisrestaurant. Some people said that this was unfair. Others supported his decision, they said they were bored of noisy children in restaurants and now they could finally have aplace for adults only .In fact , many other restaurants. have also met the same problem. So the owners tried other ways to make their restaurants quieter . Some have tried to ban children during certain times of the day. There's one restaurant in Italy. It has been creative in dealing with the problem . They rewarded (奖赏) well-behaved children to encourage parentsto control their children .These methods may be useful for a while , but it is difficult to solve this problemcompletely .依据短文内容简要回答下列问题.What is the problem for the restaurants mentioned in the passage ? ______What does the sign "NO CHILDREN"mean?______How many methods to solve the problem are mentioned in the passage ? ______What did the restaurant in Italy do to ask parents to control their children?______What do you think is a good way to solve the problem?______五、任务型阅读(本大题共 1 小题,共10.0 分)41.阅读短文,翻译划线句子.Do you often buy a lot of things you don't really need ?Do you always spend so much money on shopping?( 1)你在购物方面存在有困难吗?Do you need some advice?By reading this article ,( 2) you will not only have better shopping experience , but you will also find yourself shopping more wisely .Take a friend with you .It's easier for you to make a decision on something you buy , when someone else is giving his opinions . Go shopping with a friend or a family member who you trust for their opinions . Set a budget(估算) for yourself .你可能会发此刻购物前做个估算没实用.If it is hard for you to do this , leave your credit card at home. If your spending limit (花费上限) is 50 dollars, bring 50 dollars is enough.Make a list of the things you want .This will stop you from wasting time and money . Before you go to the stores, go online and look at the websites of your favorite stores .Go into different stores .You may go to some popular stores . However , why not try different stores ? You never know what you'll find in a little store.( 1) ______( 2) ______( 3) ______( 4) ______( 5) ______六、书面表达(本大题共 1 小题,共15.0 分)42.李华来自夏威夷的笔友Peter 是个对中国文化很感兴趣的男生.他计划2019年来中国旅行.由于素来没有到过中国,所以有点担忧.于是他便来信向李华讨教,以便做好旅行攻略.假设你是李华,请回封邮件见告他下边一些事情:1)来中国旅行的最正确时候.2)来中国后要注意的一些基本礼仪.3)到中国后建议购置的有中国特点的纪念品.注意:文章开头结尾已给出;不出现真切姓名和校名等信息;书写工整;许多于80词.Dear Peter,I am so glad to hear that you will visit China.I know you are interested in Chinese cult ure.Remember to call me when you arrive in China . I'm looking forward to your visiting.Yours , Li Hua .答案和分析1.【答案】C【分析】依据句意:辛迪能把英语讲得很好.她在伦敦已经住了好多年了.联合选项,A .一定B.不可以 C.能,选项 C 切合题意.应选:C.辛迪能把英语讲得很好.她在伦敦已经住了好多年了.熟习神态动词的基本用法,联合题意,给出答案.2.【答案】C【分析】tell" 告诉、叙述 "是动词原形,它的过去式是 told ,它的主语除第三人称的单数形式外,其余人称的主语的一般此刻时的动词的被动语态是 are told"被告诉" ,它的主语除第三人称的单数形式外,其余人称的主语的一般过去时的动词的被动语态是were told"被告诉".由题干"在大的交通事故发生后,很多孩子被告诉不要在街上嬉戏." 可知,空格是" 被告诉",用一般过去时的被动语态形式,所以用 were told ,答案应是 were told.应选:C.在大的交通事故发生后,许多孩子被告诉不要在街上嬉戏.本题考察一般过去时的被动语态的用法,在熟知所供词的含义基础上,依据句意,进而判断出正确答案.3.【答案】C【分析】help sb do 帮助某人干某事, get used to doing 习惯于干某事,deal with 办理,depend on依靠,本题依据语境:中国妈妈老是帮助孩子解决任何问题,这让孩子们习惯了依靠父亲母亲.应选:C.中国妈妈老是帮助孩子解决任何问题,这让孩子们习惯了依靠父亲母亲.本题考察动词短语,在熟知动词短语固定表达和用法基 础上,联合语境,仔细剖析,即可得出正确答案.4.【答案】 B【分析】答案:B .考察宾语从句.句意"--你能告诉我他什么 时候回来吗? --下个月.".第一个句子是 宾语从句,从句往常是 陈说语序,及主语在前,谓语在后,所以 C 不正确.依据回答 " 下个月 ",可知应当是一般未来 时态,所以 A 不正确.答案是 B .--你能告诉我他什么 时候回来吗?--下个月.宾语从句中,从句一般 为陈说语序,宾语从句的 时态和主句没有必定的 联系,需联合语境详细剖析.5.【答案】 C【分析】look up to 仰慕,be proud of 骄傲,talk back to 顶撞,regret doing 懊悔干某事,本题依据语境:当我们长大后,我们经常懊悔和父亲母亲 顶撞.应选:C .当我们长大后,我们经常懊悔和父亲母亲 顶撞.本题考察动词 短语,在熟知动词 短语固定表达和用法基 础 上,联合语境,仔细剖析,即可得出正确答案.6.【答案】 B【分析】考察叹息句.句意"我的老 师老是告诉我们知识有多重要 ".叹息句能够是what a/an+形容词+名词+主语 +谓语!或 how+形容词+主语+谓语 .主语 knowledge 知识.谓语 is .用how .形容词用 important 重要的.应选:B .我的老师老是告诉我们知识有多重要!叹息句能够用 how 或 what 指引,二者有必定差别,要掌握该知识点,而后结合语境选择正确形式,达成试题.7.【答案】A【分析】考察连词.A 假如、能否.B 除非.C 或许.联合语境:-我相信 Carmen会追上我们的.-我也这么以为.除非他在电脑游戏中迷失了自我.可知,应当是"除非 " .应选:A.-我相信 Carmen会追上我们的.-我也这么以为.除非他在电脑游戏中迷失了自我.熟习附属连词的基本用法,联合题意,给出答案.8.【答案】B【分析】dare to do敢于做某事,than 可知是比较级,故用 louder.本题依据语境:跟着年纪的增添,她敢于在讲堂上回答问题,并且她能比从前更高声地说话.应选:B.跟着年龄的增添,她敢于在讲堂上回答问题,并且她能比从前更高声地说话.本题考察动词短语,在熟知动词短语固定表达和用法基础上,联合语境,认真剖析,即可得出正确答案.9.【答案】B【分析】make sb do 让某人干某事,故第二个空填laugh,定语从句中缺主语,先行词是物,故用 that.本题依据语境:我喜爱结尾很好的动画片,它能让我发笑.应选:B.我喜爱结尾很好的动画片,它能让我发笑.本题考察关系代词,在熟知关系代词意思和用法的基础上,联合详细题目,认真剖析,即可得出正确答案.10.【答案】C【分析】That's all right 没关系;Come on 加油;With pleasure 愿意为您效力 .依据 Could you keep an eye on my luggage when I am away ,可知这里回答用 With pleasure 愿意为您效力.应选:C .--我不在的 时候,你能帮我照看一下行李 吗? --愿意为您效力.本题考察情形对话,在熟知所口供的含义基础上,依据句意,进而判断出正确答案.11.【答案】【小题 1 】C 【小题 2 】C【小题 3 C【小题 4 】B【小题 5 A6 C7 B】A9 A】B【小题 】 【小题 】 【小题 8 【小题 】 【小题 10】】【分析】1.C .考察名词.A 医生.B 厨师.C 教练.句意"他去告诉他的阵营___"..根据下一句 The next day , the coach saw a boy hiding 次日,教练看见一个男孩藏起来了.可知,应当是"教练 ".选 C .2.C .考察介词.A 在几点.B 在 上.C 在 下.句意"次日,教练看见一个男孩躲在一张大桌子 ___吃汤姆的饼干" .可知,应当是"在 下边 ".选 C .3.C .考察动词 .A 学习 .B 检查、研究.C 办理.句意"他想出了一个 ___这个问题的方法".可知,应当是"办理".选 C .4.B .考察代词.A 我.B 他.C 她.句意"好吧,是的 你要处罚 __吗,先生? ".依据上一句 Will you help me to teach him a lesson ?你能帮我 给他上一课吗? 可知,应当是 him 他.选 B .5.A .考察副词.A 耐心地.B 生气地.C 悲伤地.句意" ‘不,我不是,'教练__解释说 ".可知,应当是 "耐心地 "解说.选 A .6.C .考察动词 .A 感谢 .B 爱.C 恨.句意"那只会让他 __你" .依据上一句"the coach explained patiently""好吧,是的你要处罚他吗,先生?" 汤姆问."不,我不是," 教练耐心地解释道.可知,应当是"恨".选 C.7.B.考察名词.A 他的教练.B 他的妈妈.C 那个男孩.句意 "几日后,汤姆又收到了 __寄来的一盒饼干 ".教练和那个男孩和他在一同,不可以给他寄东西,所以应当是"他的妈妈 ".选 B.8.A .考察动词.A 偷.B 给.C 买.句意"去和 __你饼干的男孩分享吧 ".可知,应当是"偷".选 A.9.A .考察连词.A 可是.B 自从.C 固然.句意"汤姆不理解教练的企图,__他仍是遵从他的建议".可知,表示转折用 but 可是.选 A .10.B.考察形容词.A 不一样的.B 有价值的.C 廉价的.句意 "他说那几块饼干不是那么 __".依据上一句 The boy was trying to ask Tom to accept his toy robot in payment for the stolen biscuits. And Tom was refusing the gift from his newfriend.那个男孩想让汤姆接受他的玩具机器人,以支付偷来的饼干的费用.汤姆拒绝了他的新朋友送他的礼品.可知,应当是说饼干没有那么 "有价值的".选 B.这是一篇记述文,短文中的教练在得悉汤姆的饼干被偷以后,没有立刻想办法处罚这个人,而是用一种好心的方式教育了这个偷东西的孩子.使他不只认识到了自己的错误,还和汤姆成为了好朋友.进而告诉我们,在某些状况下谅解比处罚存心义.完形填空题型,抓住文章的粗心,依据上下文猜意思.联合语境,依据所给选项,判断适合的时态,人称,句型,词性、单复数变化等.选择适合答案.21.【答案】【小题 1】 C【小题2】C【分析】1. C.理解判断题.依据"Join us for our small opening at 9 am on Feb 25断图书室将于二月开放.应选 C.2. C.理解判断题.依据"We bring to the lbrary a number of good books that we hope will interest our neighbors.Books are always a gift.Never for sale!"可知,我们给图书室带来了一些好书,希望能惹起我们的街坊们的兴趣.书老是一件礼品,不卖.能够判断图书室里的书是人们送的.应选 C.本文主要介绍了一处公园内的免费图书室的由来及它的使用状况.先阅读所给的问题以及选择项,要着重句子与句子之间、段落与段落之间逻辑关系以及对篇章的整体理解.依据所给问题选择正确选项,达成试题.23.【答案】【小题 1】 B【小题2】C【分析】1. B.细节理解题.依据"Located in the city's financial and business center,2 blocks from Port of Miami ,across from Bayside Marketplace,Bayfront Park,Flagler Street shopping,and "可知,位于该市的金融和商业中心,距迈阿密港口 2 个街区,对面是海湾边市场、海滨公园、弗拉格勒街购物中心和应选B.2. C.细节理解题.依据"Nice place,clean and great services.Check in and out was fast.Location is ext remely great! Closed to everything and very convenient for our little get away trip.They also gave us teo welcoming drink vouchers! 可"知,不错的地方,洁净和很棒的服务.入住和走开都很快.地点是特别棒的!封闭的全部,我们的外出旅行特别方便.他们也给我们欢迎饮料券!能够判断酒店很便利,其余选项都不对.应选 C.3. A .细节理解题.依据"For more information,www.Travelocity .come"可知,有关更多信息,请单击该链接 Ju20.2018 www .Travelocity .come.应选 A .本文是迈阿密 YVE 酒店的广告,介绍了它的地址、特点和客人的评论等.先阅读所给的问题以及选择项,要着重句子与句子之间、段落与段落之间逻辑关系以及对篇章的整体理解.依据所给问题选择正确选项,达成试题.25.【答案】【小题 1】 A【小题2】C【小题3】A【小题4】C【小题5】B【分析】1.A 细节理解题.依据 Now Huawei has got third place at the mobile market,just following Apple and Samsung.此刻,华为在手机市场排名第三,仅次于苹果和三星.可知依据文章,三星和苹果是当前最大的两家智好手机企业.故选 A .2.C 词义猜想题.依据前句 Now Huawei has got third place at the mobilemarket, just following Apple and Samsung. After seeing more of its smartphones were sold last year, Huawei appears to be more confident in itsbigger goals.此刻,华为在挪动市场上排名第三,仅次于苹果和三星.在看到昨年智好手机销量增添后,华为仿佛对其更大的目标更有信心.可知联合选项,应说我们希望在三年内,我们的市场份额能排在前二位,在五年内,我们的市场份额能排在前一位, "所以 "share" 意为份额.应选 C.3.A 细节理解题.依据 The company sold 108 million smartphones in 2015,该企业 2015 年销售了 1.08 亿部智好手机,可知 2015 年销售了 1.08 亿部智好手机,应选 A.4.C 细节判断题.依据 Yu said that the company was "so late" to theUS. However, we are trying hard to raise our market share there in the next few俞说华为对过们years.,美国 "太晚了 ".不,我正努力在未来几年提升在那边的市场份额华为正在努力提升其在美国的市场份额选.可知.故 C.5.B 要旨概括题.依据整篇文章内容及其句子 But now in China and even in the world, Huawei is a wonder. Although it started producing mobile phones not many years ago, it has become one of the most famous phone companies.但此刻在中国以致世界,华为是一个奇观.只管华为在几年前就开始生产手机,但它已经成为最有名的电话企业之一.可知华为的手机企业愈来愈好.故选 B.短文讲了华为在挪动市场上排名第三,仅次于苹果和三星.详尽的介绍了华为手机这几年的发展状况和对未来的计划.在通读全文的基础上,依据全文粗心,睁开逻辑思想,前怕狼后怕虎,认真察看选项,认真斟酌,确立最正确答案.30.【答案】【小题 1】 C【小题2】A【小题3】B【小题4】B【小题5】C【分析】1.C 内容推测题.依据"Neurons in your skin send this information to your brain"皮肤中的神经元以每小时 240 多公里的速度将这些信息发送到大脑,可知神经元能够发送信息到大脑中,C 项切合题意,应选 C.2.A 内容推测题.依据"No computer has your brain's unbelievable ability to deal with the amount of inf ormation coming from your eyes,ears and other sensory organs"没有一台电脑能像你的大脑那样办理来自眼睛、耳朵和其余感觉器官的大批信息,文章主要经过与电脑进行比较来告诉我们大脑的工作速度有多快, A 项切合题意.应选 A.3.B 细节理解题.依据"The structure of your brain changes every time you have a new thought"每当你有一个新的想法,你的大脑构造就会改变,可知当有新想法的时候,大脑结构会改变,应选 B.4.B 细节理解题.依据"As you practice,your brain sends "bike riding" messages again and again.Soo n,the actions are learnt and you are able to ride a bike easily from then on"当你会了,可知学习新技术时,大脑会一遍一遍地发送信息,应选 B.5.C 要旨粗心题.整篇文章主要讲了人类大脑的奇特之处,它是怎样工作的等,文章第一段"It is so amazing that a famous scientist once called it "the most complex thing w e have yet discovered in our universe".它是这样奇特,一位有名的科学家曾经称之为"在我们的宇宙中间还未发现过的最复杂的东西",C 项人类大脑这个不行思议的器官,切合题意,应选 C.你的大脑控制着你所做的全部.它使你能够思虑、学习、创建和感觉,眨眼和呼吸的控制中心是你的大脑.它是这样奇特,一位有名的科学家曾经称之为" 在我们的宇宙中间还未发现过的最复杂的东西 ".这个小器官,重量不到一公斤半,真的能做这么多吗?令人惊讶的是,你的大脑含有大概 1000 亿个神经元 --你要花 3000 多年才能数完.信不信由你,你大脑中的活动从未停止过.你的神经元创建和发送的信息比世界上全部的电话都多.固然一个神经元只好产生少许的电流,可是全部的神经元加在一同能够产生足够的电流来驱动一个灯泡.那么你的大脑究竟有多快?想象一下:一只蜜蜂落在你的脚上.皮肤中的神经元以每小时 240 多公里的速度将这些信息发送到大脑.而后你的大脑用其余神经元把信息发送回你的脚,让蜜蜂快速走开.这些神经元能够以每小时 320 公里的速度发送信息.没有一台电脑能像你的大脑那样办理来自眼睛、耳朵和其余感觉器官的大批信息.可是你的大脑是怎样让你学习未来会用到的东西的呢?每当你有一个新的想法,记着或学到一些东西,你的大脑构造就会改变.比如,开初骑自行车仿佛不行能,但很快你就能做到.怎样?当你练习时,你的大脑一次又一次地发送"骑自行车"的信息.很快,这些动作就学会了,从那时起你就能轻松地骑自行车了.第一认真阅读短文,掌握粗心,而后联合详细的题目再读短文,从中找出有【小题 1】 C【小题2】A【小题3】A【小题4】C【小题5】C【分析】1.C 细节理解题.依据 He could also read and write French, Hebrew, Latin ,and ancient Greek besides English when he was at school.他在学校时除了英语外,还能够读写法语、希伯来语、拉丁语和古希腊语.可知会五种语言.应选C.2.A 细节理解题.依据 Since 2010, many people think Zuckerberg is one of the wealthiest and most influential people in the world.自2010 年以来,很多人以为扎克伯格是世界上最富裕和最有影响力的人之一.可知以为他在世界上有很大的影响力.应选 A .3.A 细节理解题.依据 On Mar 18 th , 2016, while visiting Beijing , Heposted on facebook, "It's great to be back in Beijing! I started my visit with a run through Tiananmen Square, past the Forbidden City and over to the Temple ofHeaven." 2016 年 3 月 18 日,在北京接见时期,他在 facebook上写道:" 回到北京真好 !" 我以跑过天安门广场、故宫和天坛开始了我的旅途.可知没有清华大学.应选 A .4.C 细节理解题.依据 Mark Zuckerberg, is an American computer programmer, CEO, and founder(首创人) of Facebook. His net worth is about US $ 58.6 billion , ranking him the fifth richest person in the world.马克?扎克伯格是美国电脑程序员、首席履行官和 Facebook的首创人(首创者).他的净财产约 586 亿美元,是世界第五富裕的人.可知扎克伯格此刻特别成功.应选C.5.C 细节判断题.依据 In 2003, Zuckerberg met Priscilla Chan, at a party during his second year at Harvard. In 2010, they got married and had their first baby. 2003 年,扎克伯格在哈佛大学第二年的一次聚会上碰到了陈丽晶.2010 年,他们成婚并生了第一个孩子. Last year, Zuckerberg finally。
湖南省株洲市芦淞区九年级上学期语文期末考试试卷

湖南省株洲市芦淞区九年级上学期语文期末考试试卷姓名:________ 班级:________ 成绩:________一、选择题 (共2题;共4分)1. (2分)下列加横线的字注音无误的一项是()。
A . 唾手可得(tuò) 济南(jì) 模糊(mó) 辛酸(suān)B . 寄人篱下(lí) 牛圈(quān) 掰了(bāi) 后悔(huǐ)C . 孤苦伶仃(líng) 下咽(yàn) 宁大嫂(níng) 蹲下(dūn)D . 立锥之地(zhuī) 有恃无恐(shì) 誓虑(shì) 名誉(yù)2. (2分)划线字字义解释有误的一项是()A . 驯良(顺服)安然无恙(病)终年累月(堆积)B . 鸟瞰(俯视)姹紫嫣红(娇艳)执迷不悟(坚持)C . 业已(已经)漠不关心(冷淡)稍逊风骚(差)D . 匝道(周)心旷神怡(空阔)一张一翕(合)二、字词书写 (共1题;共2分)3. (2分)(2019·荆州) 请在横线上填入恰当的汉字。
这时候,雨已经化了妆,它经常变成美丽的雪花,飘然lì________临人间。
但在南国,雨仍然偶尔造访大地,但它变得更吝sè________了。
三、句子默写 (共1题;共10分)4. (10分)(2019·包头) 默写。
(1) ________,路远莫致之。
(《庭中有奇树》)(2)晴空一鹤排云上,________。
(刘禹锡《秋词》)(3) ________,学诗谩有惊人句。
(李清照《渔家傲》)(4)纷纷暮雪下辕门,________。
(岑参《白雪歌送武判官归京》)(5)鹏之徙于南冥也,水击三千里,________,去以六月息者也。
(《北冥有鱼》)(6)《醉翁亭记》中,凝练传神地写出山中早晚的阴晴交化,其中写晨景的语句是________。
(7)《木兰诗》中“________,________”描写了木兰在边塞军宫艰苦战斗生活画面。
湖南省株洲市九年级上学期数学期末考试试卷

湖南省株洲市九年级上学期数学期末考试试卷姓名:________ 班级:________ 成绩:________一、单选题 (共10题;共20分)1. (2分) (2019八上·房山期中) 下列根式中属于最简二次根式的是()A .B .C .D .2. (2分) (2016九上·越秀期末) 方程的根的情况是()A . 有两个不相等的实数根B . 有两个相等的实数根C . 没有实数根D . 无法确定是否有实数根3. (2分) (2018九上·吴兴期末) 若△ABC的每条边长增加各自的10%得到△A′B′C′,则∠B′的度数与其对应角∠B的度数相比()A . 增加了10%B . 减少了10%C . 增加了(1+10%)D . 没有改变4. (2分)比较tan46°,cos29°,sin59°的大小关系是()A . tan46°<cos29°<sin59°B . tan46°<sin59°<cos29°C . sin59°<tan46°<cos29°D . sin59°<cos29°<tan46°5. (2分)已知关于x的方程x2-kx-6=0的一个根为x=3,则实数k的值为()A . 1B .C . 2D .6. (2分) (2020九上·莘县期末) 下列诗句所描述的事件中,是不可能事件的是()A . 黄河人海流B . 锄禾日当午C . 大漠孤烟直D . 手可摘星辰7. (2分)(2018·河北模拟) 如图,△ABC中,D,E是BC边上的点,BD:DE:EC=3:2:1,M在AC边上,CM:MA=1:2,BM交AD,AE于H,G,则BH:HG:GM等于()A . 4:2:1B . 5:3:1C . 25:12:5D . 51:24:108. (2分)如图,已知一坡面的坡度i=1:,则坡角α为()A . 15°B . 20°C . 30°D . 45°9. (2分)在Rt△ABC中,∠C=90°,若sinA=,则∠A的度数是A . 30°B . 45°C . 60°D . 90°10. (2分)(2017·福田模拟) 如图,已知E′(2,-1),F′(,),以原点O为位似中心,按比例尺1:2把△E′F′O扩大,则E′点对应点E的坐标为()A . (-4,2)B . (4,-2)C . (-1,-1)D . (-1,4)二、填空题 (共5题;共5分)11. (1分) (2016七下·临泽开学考) 若3a2-a-2=0,则5+2a-6a2=________12. (1分) (2018九上·长沙期中) 对于实数a,b,定义运算“﹡”:a﹡b= ,例如4﹡2,因为4>2,所以4﹡2=42﹣4×2=8.若x1 , x2是一元二次方程x2﹣5x+6=0的两个根,则x1﹡x2=________.13. (1分) (2019八上·泰州月考) 已知三角形中,则斜边上的高为________.14. (1分) (2019八下·海淀期中) 如果直线y=-2x+k与两坐标轴围成的三角形面积是8,则k的值为________.15. (1分)(2019·重庆模拟) 在矩形ABCD中,AB=4,BC=3,取CD中点E,连接BD、BE,将沿BE翻折成为,过点C作CM⊥BF于M,则CM+FC=________.三、解答题 (共8题;共59分)16. (5分)已知,,。
九年级上册株洲数学期末试卷测试卷(解析版)

九年级上册株洲数学期末试卷测试卷(解析版)一、选择题1.有9名同学参加歌咏比赛,他们的预赛成绩各不相同,现取其中前4名参加决赛,小红同学在知道自己成绩的情况下,要判断自己能否进入决赛,还需要知道这9名同学成绩的( ) A .平均数B .方差C .中位数D .极差2.如图,ABC ∆与A B C '''∆是以坐标原点O 为位似中心的位似图形,若点A 是OA '的中点,ABC ∆的面积是6,则A B C '''∆的面积为( )A .9B .12C .18D .243.若将半径为24cm 的半圆形纸片围成一个圆锥的侧面,则这个圆锥的底面圆半径为( ) A .3cmB .6cmC .12cmD .24cm4.如图,在平面直角坐标系xOy 中,点A 为(0,3),点B 为(2,1),点C 为(2,-3).则经画图操作可知:△ABC 的外心坐标应是( )A .()0,0B .()1,0C .()2,1--D .()2,0 5.已知一元二次方程x 2+kx-3=0有一个根为1,则k 的值为( ) A .−2B .2C .−4D .46.△ABC 的外接圆圆心是该三角形( )的交点.A .三条边垂直平分线B .三条中线C .三条角平分线D .三条高7.如图,AB 是O 的直径,AC 切O 于点A ,若70C ∠=︒,则AOD ∠的度数为( )A .40°B .45°C .60°D .70°8.生产季节性产品的企业,当它的产品无利润时就会及时停产.现有一生产季节性产品的企业,一年中获得利润y 与月份n 之间的函数关系式是y =-n 2+15n -36,那么该 企业一年中应停产的月份是( ) A .1月,2月 B .1月,2月,3月 C .3月,12月D .1月,2月,3月,12月9.某果园2011年水果产量为100吨,2013年水果产量为144吨,求该果园水果产量的年平均增长率.设该果园水果产量的年平均增长率为x ,则根据题意可列方程为( ) A .144(1﹣x )2=100 B .100(1﹣x )2=144 C .144(1+x )2=100 D .100(1+x )2=144 10.把函数212y x =-的图象,经过怎样的平移变换以后,可以得到函数()21112y x =--+的图象( ) A .向左平移1个单位,再向下平移1个单位 B .向左平移1个单位,再向上平移1个单位 C .向右平移1个单位,再向上平移1个单位 D .向右平移1个单位,再向下平移1个单位11.如图,在O 中,AB 是O 的直径,点D 是O 上一点,点C 是弧AD 的中点,弦CE AB ⊥于点F ,过点D 的切线交EC 的延长线于点G ,连接AD ,分别交CF BC 、于点P Q 、,连接AC .给出下列结论:①BAD ABC ∠=∠;②GP GD =;③点P 是ACQ的外心;④AP AD ⋅CQ CB =⋅.其中正确的是( )A .①②③B .②③④C .①③④D .①②③④12.如图,点P (x ,y )(x >0)是反比例函数y=kx(k >0)的图象上的一个动点,以点P 为圆心,OP 为半径的圆与x 轴的正半轴交于点A ,若△OPA 的面积为S ,则当x 增大时,S 的变化情况是( )A .S 的值增大B .S 的值减小C .S 的值先增大,后减小D .S 的值不变二、填空题13.如图,A 、B 、C 是⊙O 上三点,∠ACB =30°,则∠AOB 的度数是_____.14.圆锥的母线长为5cm ,高为4cm ,则该圆锥的全面积为_______cm 2.15.如图,已知菱形ABCD 中,4AB =,C ∠为钝角,AM BC ⊥于点M ,N 为AB 的中点,连接DN ,MN .若90DNM ∠=︒,则过M 、N 、D 三点的外接圆半径为______.16.将正整数按照图示方式排列,请写出“2020”在第_____行左起第_____个数.17.如图,∠C=∠E=90°,AC=3,BC=4,AE=2,则AD=_________ .18.已知圆锥的侧面积为20πcm 2,母线长为5cm ,则圆锥底面半径为______cm . 19.如图(1),在矩形ABCD 中,将矩形折叠,使点B 落在边AD 上,这时折痕与边AD 和BC 分别交于点E 、点F .然后再展开铺平,以B 、E 、F 为顶点的△BEF 称为矩形ABCD 的“折痕三角形”.如图(2),在矩形ABCD 中,AB=2,BC=4,当“折痕△BEF”面积最大时,点E 的坐标为_________________________.20.某小区2019年的绿化面积为3000m 2,计划2021年的绿化面积为4320m 2,如果每年绿化面积的增长率相同,设增长率为x ,则可列方程为______.21.如图,ABC 是⊙O 的内接三角形,AD 是△ABC 的高,AE 是⊙O 的直径,且AE=4,若CD=1,AD=3,则AB 的长为______.22.已知二次函数2(0)y ax bx c a =++≠,y 与x 的部分对应值如下表所示:x… -1 0 1 2 3 4 … y…61-2-3-2m…下面有四个论断:①抛物线2(0)y ax bx c a =++≠的顶点为(23)-,; ②240b ac -=;③关于x 的方程2=2ax bx c ++-的解为12=13x x =,;④=3m .其中,正确的有___________________.23.如图,在⊙O中,分别将弧AB、弧CD沿两条互相平行的弦AB、CD折叠,折叠后的弧均过圆心,若⊙O的半径为4,则四边形ABCD的面积是__________________.24.如图,四边形ABCD中,∠A=∠B=90°,AB=5cm,AD=3cm,BC=2cm,P是AB 上一点,若以P、A、D为顶点的三角形与△PBC相似,则PA=_____cm.三、解答题25.如图,四边形ABCD内接于⊙O,AC为⊙O的直径,D为AC的中点,过点D作DE∥AC,交BC的延长线于点E.(1)判断DE与⊙O的位置关系,并说明理由;(2)若CE=163,AB=6,求⊙O的半径.26.在矩形ABCD中,AB=3,AD=5,E是射线..DC上的点,连接AE,将△ADE沿直线AE 翻折得△AFE.(1)如图①,点F恰好在BC上,求证:△ABF∽△FCE;(2)如图②,点F在矩形ABCD内,连接CF,若DE=1,求△EFC的面积;(3)若以点E、F、C为顶点的三角形是直角三角形,则DE的长为.27.如图,宾馆大厅的天花板上挂有一盏吊灯AB,某人从C点测得吊灯顶端A的仰角为35︒,吊灯底端B的仰角为30,从C点沿水平方向前进6米到达点D,测得吊灯底端B 的仰角为60︒.请根据以上数据求出吊灯AB的长度.(结果精确到0.1米.参考数据:sin35°≈0.57,cos35°≈0.82,tan35°≈0.70,2≈1.41,3≈1.73)28.如图,矩形OABC中,A(6,0)、C(0,23)、D(0,33),射线l过点D且与x轴平行,点P、Q分别是l和x轴正半轴上动点,满足∠PQO=60°.(1)①点B的坐标是;②当点Q与点A重合时,点P的坐标为;(2)设点P的横坐标为x,△OPQ与矩形OABC的重叠部分的面积为S,试求S与x的函数关系式及相应的自变量x的取值范围.29.如图1,水平放置一个三角板和一个量角器,三角板的边AB和量角器的直径DE在一条直线上,∠ACB=90°,∠BAC=30°,OD=3cm,开始的时候BD=1cm,现在三角板以2cm/s 的速度向右移动.(1)当点B于点O重合的时候,求三角板运动的时间;(2)三角板继续向右运动,当B点和E点重合时,AC与半圆相切于点F,连接EF,如图2所示.①求证:EF平分∠AEC;②求EF的长.30.如图,四边形ABCD内接于⊙O,AC为⊙O的直径,D为AC的中点,过点D作DE∥AC,交BC的延长线于点E.(1)判断DE与⊙O的位置关系,并说明理由;(2)若CE=163,AB=6,求⊙O的半径.31.如图①,抛物线y=x2﹣(a+1)x+a与x轴交于A、B两点(点A位于点B的左侧),与y轴交于点C.已知△ABC的面积为6.(1)求这条抛物线相应的函数表达式;(2)在抛物线上是否存在一点P,使得∠POB=∠CBO,若存在,请求出点P的坐标;若不存在,请说明理由;(3)如图②,M是抛物线上一点,N是射线CA上的一点,且M、N两点均在第二象限内,A、N是位于直线BM同侧的不同两点.若点M到x轴的距离为d,△MNB的面积为2d,且∠MAN=∠ANB,求点N的坐标.32.如图示,AB是O的直径,点F是半圆上的一动点(F不与A,B重合),弦AD平分BAF∠,过点D作DE AF⊥交射线AF于点AF.(1)求证:DE 与O 相切:(2)若8AE =,10AB =,求DE 长;(3)若10AB =,AF 长记为x ,EF 长记为y ,求y 与x 之间的函数关系式,并求出AF EF ⋅的最大值.【参考答案】***试卷处理标记,请不要删除一、选择题 1.C 解析:C 【解析】 【分析】9人成绩的中位数是第5名的成绩.参赛选手要想知道自己是否能进入前4名,只需要了解自己的成绩以及全部成绩的中位数,比较即可. 【详解】由于总共有9个人,且他们的分数互不相同,第5的成绩是中位数,要判断是否进入前5名,故应知道中位数的多少. 故选:C . 【点睛】此题主要考查统计的有关知识,主要包括平均数、中位数、极差、方差的意义,掌握相关知识点是解答此题的关键.2.D解析:D 【解析】 【分析】根据位似图形的性质,再结合点A 与点A '的坐标关系可得出两个三角形的相似比,再根据面积比等于相似比的平方即可得出答案. 【详解】解:∵△ABC 与△A B C '''是以坐标原点O 为位似中心的位似图形,且A 为O A '的中心, ∴△ABC 与△A B C '''的相似比为:1:2;∵位似图形的面积比等于相似比的平方,∴△A B C '''的面积等于4倍的△ABC 的面积,即4624⨯=. 故答案为:D. 【点睛】本题考查的知识点是位似图形的性质,位似是特殊的相似,熟记位似图形的面积比等于相似比的平方是解题的关键.3.C解析:C 【解析】 【分析】易得圆锥的母线长为24cm ,以及圆锥的侧面展开图的弧长,也就是圆锥的底面周长,除以2π即为圆锥的底面半径. 【详解】解:圆锥的侧面展开图的弧长为:2π24224π⨯÷=, ∴圆锥的底面半径为:()24π2π12cm ÷=. 故答案为:C. 【点睛】本题考查的知识点是圆锥的有关计算,熟记各计算公式是解题的关键.4.C解析:C 【解析】外心在BC 的垂直平分线上,则外心纵坐标为-1.故选C.5.B解析:B 【解析】分析:根据一元二次方程的解的定义,把x=1代入方程得关于k 的一次方程1-3+k=0,然后解一次方程即可.详解:把x=1代入方程得1+k-3=0, 解得k=2. 故选B .点睛:本题考查了一元二次方程的解:能使一元二次方程左右两边相等的未知数的值是一元二次方程的解.6.A解析:A 【解析】 【分析】根据三角形的外接圆的概念、三角形的外心的概念和性质直接填写即可. 【详解】解:△ABC的外接圆圆心是△ABC三边垂直平分线的交点,故选:A.【点睛】本题考查了三角形的外心,三角形的外接圆圆心即为三角形的外心,是三条边垂直平分线的交点,正确理解三角形外心的概念是解题的关键.7.A解析:A【解析】【分析】先依据切线的性质求得∠CAB的度数,然后依据直角三角形两锐角互余的性质得到∠CBA 的度数,然后由圆周角定理可求得∠AOD的度数.【详解】解:∵AC是圆O的切线,AB是圆O的直径,∴AB⊥AC,∴∠CAB=90°,又∵∠C=70°,∴∠CBA=20°,∴∠AOD=40°.故选:A.【点睛】本题主要考查的是切线的性质、圆周角定理、直角三角形的性质,求得∠CBA=20°是解题的关键.8.D解析:D【解析】【分析】【详解】当-n2+15n-36≤0时该企业应停产,即n2-15n+36≥0,n2-15n+36=0的两个解是3或者12,根据函数图象当n≥12或n≤3时n2-15n+36≥0,所以1月,2月,3月,12月应停产.故选D9.D解析:D【解析】试题分析:2013年的产量=2011年的产量×(1+年平均增长率)2,把相关数值代入即可.解:2012年的产量为100(1+x),2013年的产量为100(1+x)(1+x)=100(1+x)2,即所列的方程为100(1+x)2=144,故选D.点评:考查列一元二次方程;得到2013年产量的等量关系是解决本题的关键.10.C解析:C【解析】【分析】根据抛物线顶点的变换规律作出正确的选项.【详解】 抛物线212y x =-的顶点坐标是00(,),抛物线线()21112y x =--+的顶点坐标是11(,), 所以将顶点00(,)向右平移1个单位,再向上平移1个单位得到顶点11(,), 即将函数212y x =-的图象向右平移1个单位,再向上平移1个单位得到函数()21112y x =--+的图象. 故选:C .【点睛】 主要考查了函数图象的平移,要求熟练掌握平移的规律:左加右减,上加下减.并用规律求函数解析式.11.B解析:B【解析】【分析】①由于AC 与BD 不一定相等,根据圆周角定理可判断①;②连接OD ,利用切线的性质,可得出∠GPD=∠GDP ,利用等角对等边可得出GP=GD ,可判断②;③先由垂径定理得到A 为CE 的中点,再由C 为AD 的中点,得到CD AE =,根据等弧所对的圆周角相等可得出∠CAP=∠ACP ,利用等角对等边可得出AP=CP ,又AB 为直径得到∠ACQ 为直角,由等角的余角相等可得出∠PCQ=∠PQC ,得出CP=PQ ,即P 为直角三角形ACQ 斜边上的中点,即为直角三角形ACQ 的外心,可判断③;④正确.证明△APF ∽△ABD ,可得AP×AD=AF×AB ,证明△ACF ∽△ABC ,可得AC 2=AF×AB ,证明△CAQ ∽△CBA ,可得AC 2=CQ×CB ,由此即可判断④;【详解】解:①错误,假设BAD ABC ∠=∠,则BD AC =,AC CD =,∴AC CD BD ==,显然不可能,故①错误.②正确.连接OD . GD 是切线,DG OD ∴⊥,∴∠+∠=︒,GDP ADO90=,OA OD∴∠=∠,ADO OAD∠=∠,∠+∠=︒,GPD APFAPF OAD90∴∠=∠,GPD GDP∴=,故②正确.GD GP⊥,③正确.AB CE∴AE AC=,=,AC CD∴CD AE=,∴∠=∠,CAD ACEPC PA∴=,AB是直径,∴∠=︒,90ACQCAP CQP∠+∠=︒,∴∠+∠=︒,90 ACP QCP90∴∠=∠,PCQ PQC∴==,PC PQ PA∠=︒,ACQ90∆的外心.故③正确.∴点P是ACQ④正确.连接BD.∠=∠=︒,PAF BAD90AFP ADB∠=∠,APF ABD∽,∴∆∆∴AP AF=,AB ADAP AD AF AB∴⋅=⋅,∠=∠=︒,AFC ACBCAF BAC∠=∠,90∴∆∆∽,ACF ABC可得2=,AC AF AB∠=∠,∠=∠,CAQ ABCACQ ACB∽,可得2∴∆∆CAQ CBA=⋅,AC CQ CBAP AD CQ CB∴⋅=⋅.故④正确,故选:B.【点睛】本题考查相似三角形的判定和性质、垂径定理、圆周角定理、切线的性质等知识,解题的关键是正确现在在相似三角形解决问题,属于中考选择题中的压轴题.12.D解析:D【解析】【分析】作PB⊥OA于B,如图,根据垂径定理得到OB=AB,则S△POB=S△PAB,再根据反比例函数k的几何意义得到S△POB=12|k|,所以S=2k,为定值.【详解】作PB⊥OA于B,如图,则OB=AB,∴S△POB=S△PAB.∵S△POB=12|k|,∴S=2k,∴S的值为定值.故选D.【点睛】本题考查了反比例函数系数k的几何意义:在反比例函数y=kx图象中任取一点,过这一个点向x轴和y轴分别作垂线,与坐标轴围成的矩形的面积是定值|k|.二、填空题13.60°【解析】【分析】直接利用圆周角定理,即可求得答案.【详解】∵A、B、C是⊙O上三点,∠ACB=30°,∴∠AOB的度数是:∠AOB =2∠ACB=60°.故答案为:60°.【点解析:60°【解析】【分析】直接利用圆周角定理,即可求得答案.【详解】∵A、B、C是⊙O上三点,∠ACB=30°,∴∠AOB的度数是:∠AOB=2∠ACB=60°.故答案为:60°.【点睛】考查了圆周角定理的运用,同弧或等弧所对的圆周角等于圆心角的一半.14.24π【解析】【分析】利用圆锥的母线长和圆锥的高求得圆锥的底面半径,表面积=底面积+侧面积=π×底面半径2+底面周长×母线长÷2.【详解】解:∵圆锥母线长为5cm,圆锥的高为4cm,∴底解析:24π【解析】【分析】利用圆锥的母线长和圆锥的高求得圆锥的底面半径,表面积=底面积+侧面积=π×底面半径2+底面周长×母线长÷2.【详解】解:∵圆锥母线长为5cm,圆锥的高为4cm,∴底面圆的半径为3,则底面周长=6π,∴侧面面积=12×6π×5=15π;∴底面积为=9π,∴全面积为:15π+9π=24π.故答案为24π.【点睛】本题利用了圆的周长公式和扇形面积公式求解.15.【解析】【分析】通过延长MN 交DA 延长线于点E ,DF⊥BC,构造全等三角形,根据全等性质证出DE=DM,,再通过AE=BM=CF,在Rt△DMF 和Rt△DCF 中,利用勾股定理列方程求DM 长,根1【解析】【分析】通过延长MN 交DA 延长线于点E ,DF ⊥BC,构造全等三角形,根据全等性质证出DE=DM,,再通过AE=BM=CF,在Rt △DMF 和Rt △DCF 中,利用勾股定理列方程求DM 长,根据圆的性质即可求解.【详解】如图,延长MN 交DA 延长线于点E ,过D 作DF ⊥BC 交BC 延长线于F,连接MD,∵四边形ABCD 是菱形,∴AB=BC=CD=4,AD ∥BC,∴∠E=∠EMB, ∠EAN=∠NBM,∵AN=BN,∴△EAN ≌BMN,∴AE=BM,EN=MN,∵90DNM ∠=︒,∴DN ⊥EM,∴DE=DM,∵AM ⊥BC,DF ⊥BC,AB=DC,AM=DF∴△ABM ≌△DCF,∴BM=CF,设BM=x,则DE=DM=4+x,在Rt △DMF 中,由勾股定理得,DF 2=DM 2-MF 2=(4+x)2-42,在Rt △DCF 中,由勾股定理得,DF 2=DC 2-CF 2=4 2-x 2,∴(4+x)2-42=4 2-x 2,解得,x 1=2,x 2=232(不符合题意,舍去)∴DM=2,∴90DNM ∠=︒∴过M 、N 、D 三点的外接圆的直径为线段DM, ∴其外接圆的半径长为1312DM .31.【点睛】本题考查菱形的性质,全等的判定与性质,勾股定理及圆的性质的综合题目,根据已知条件结合图形找到对应的知识点,通过“倍长中线”构建“X字型”全等模型是解答此题的突破口,也是解答此题的关键.16.4【解析】【分析】根据图形中的数字,可以写出前n行的数字之和,然后即可计算出2020在多少行左起第几个数字,本题得以解决.【详解】解:由图可知,第一行1个数,第二行2个数,第解析:4【解析】【分析】根据图形中的数字,可以写出前n行的数字之和,然后即可计算出2020在多少行左起第几个数字,本题得以解决.【详解】解:由图可知,第一行1个数,第二行2个数,第三行3个数,…,则第n行n个数,故前n个数字的个数为:1+2+3+…+n=(1)2n n+,∵当n=63时,前63行共有63642⨯=2016个数字,2020﹣2016=4,∴2020在第64行左起第4个数,故答案为:64,4.【点睛】本题考查了数字类规律探究,从已有数字确定其变化规律是解题的关键.17..【解析】试题分析:由∠C=∠E=90°,∠BAC=∠DAE可得△ABC∽△ADE,根据相似三角形的对应边的比相等就可求出AD的长.试题解析:∵∠C=∠E=90°,∠BAC=∠DAE∴△AB解析:10 3.【解析】试题分析:由∠C=∠E=90°,∠BAC=∠DAE可得△ABC∽△ADE,根据相似三角形的对应边的比相等就可求出AD的长.试题解析:∵∠C=∠E=90°,∠BAC=∠DAE∴△ABC∽△ADE∴AC:AE=BC:DE∴DE=83∴103AD=考点: 1.相似三角形的判定与性质;2.勾股定理.18.4【解析】【分析】由圆锥的母线长是5cm,侧面积是20πcm2,求圆锥侧面展开扇形的弧长,然后再根据锥的侧面展开扇形的弧长等于圆锥的底面周长求解.【详解】解:由圆锥的母线长是5cm,侧面积解析:4【解析】【分析】由圆锥的母线长是5cm,侧面积是20πcm2,求圆锥侧面展开扇形的弧长,然后再根据锥的侧面展开扇形的弧长等于圆锥的底面周长求解.【详解】解:由圆锥的母线长是5cm,侧面积是20πcm2,根据圆锥的侧面展开扇形的弧长为:2405Slrπ===8π,再根据锥的侧面展开扇形的弧长等于圆锥的底面周长,可得822lrπππ===4cm.故答案为:4.【点睛】本题考查圆锥的计算,掌握公式正确计算是解题关键.19.(,2).【解析】【分析】【详解】解:如图,当点B与点D重合时,△BEF面积最大,设BE=DE=x,则AE=4-x,在RT△ABE中,∵EA2+AB2=BE2,∴(4-x)2+22=解析:(32,2).【解析】【分析】【详解】解:如图,当点B与点D重合时,△BEF面积最大,设BE=DE=x,则AE=4-x,在RT△ABE中,∵EA2+AB2=BE2,∴(4-x)2+22=x2,∴x=52,∴BE=ED=52,AE=AD-ED=32,∴点E坐标(32,2).故答案为:(32,2).【点睛】本题考查翻折变换(折叠问题),利用数形结合思想解题是关键.20.3000(1+ x)2=4320【解析】【分析】设增长率为x,则2010年绿化面积为3000(1+x)m2,则2021年的绿化面积为3000(1+x)(1+x)m2,然后可得方程.【详解】解析:3000(1+ x)2=4320【解析】【分析】设增长率为x,则2010年绿化面积为3000(1+x)m2,则2021年的绿化面积为3000(1+x)(1+x)m2,然后可得方程.【详解】解:设增长率为x,由题意得:3000(1+x)2=4320,故答案为:3000(1+x)2=4320.【点睛】本题考查了由实际问题抽象出一元二次方程,关键是正确理解题意,找出题目中的等量关系.21.【解析】【分析】利用勾股定理求出AC,证明△ABE∽△ADC,推出,由此即可解决问题.【详解】解:∵AD是△ABC的高,∴∠ADC=90°,∴,∵AE是直径,∴∠ABE=90°,【解析】【分析】利用勾股定理求出AC ,证明△ABE ∽△ADC ,推出AB AE AD AC =,由此即可解决问题. 【详解】解:∵AD 是△ABC 的高,∴∠ADC=90°,∴AC ==∵AE 是直径,∴∠ABE=90°,∴∠ABE=∠ADC ,∵∠E=∠C ,∴△ABE ∽△ADC , ∴AB AE AD AC=, ∴3AB =∴AB =故答案为:5 【点睛】本题考查相似三角形的判定和性质,勾股定理、圆周角定理等知识,解题的关键是正确寻找相似三角形解决问题.22.①③.【解析】【分析】根据图表求出函数对称轴,再根据图表信息和二次函数性质逐一判断即可.【详解】由二次函数y =ax2+bx+c (a≠0),y 与x 的部分对应值可知:该函数图象是开口向上的抛解析:①③.【解析】【分析】根据图表求出函数对称轴,再根据图表信息和二次函数性质逐一判断即可.【详解】由二次函数y =ax 2+bx+c (a≠0),y 与x 的部分对应值可知:该函数图象是开口向上的抛物线,对称轴是直线x=2,顶点坐标为(2,-3);与x轴有两个交点,一个在0与1之间,另一个在3与4之间;当y=-2时,x=1或x=3;由抛物线的对称性可知,m=1;∴①抛物线y=ax2+bx+c(a≠0)的顶点为(2,-3),结论正确;②b2﹣4ac=0,结论错误,应该是b2﹣4ac>0;③关于x的方程ax2+bx+c=﹣2的解为x1=1,x2=3,结论正确;④m=﹣3,结论错误,∴其中,正确的有. ①③故答案为:①③【点睛】本题考查了二次函数的图像,结合图表信息是解题的关键.23.【解析】【分析】作OH⊥AB,延长OH交于E,反向延长OH交CD于G,交于F,连接OA、OB、OC、OD,根据折叠的对称性及三角形全等,证明AB=CD,又因AB∥CD,所以四边形ABCD是平行解析:163【解析】【分析】作OH⊥AB,延长OH交O于E,反向延长OH交CD于G,交O于F,连接OA、OB、OC、OD,根据折叠的对称性及三角形全等,证明AB=CD,又因AB∥CD,所以四边形ABCD 是平行四边形,由平行四边形面积公式即可得解.【详解】如图,作OH⊥AB,垂足为H,延长OH交O于E,反向延长OH交CD于G,交O于F,连接OA、OB、OC、OD,则OA=OB=OC=OD=OE=OF=4,∵弧AB、弧CD沿两条互相平行的弦AB、CD折叠,折叠后的弧均过圆心,∴OH=HE=1×4=22,OG=GF=1×4=22,即OH=OG,又∵OB=OD,∴Rt△OHB≌Rt△OGD,∴HB=GD,同理,可得AH=CG= HB=GD∴AB=CD又∵AB ∥CD∴四边形ABCD 是平行四边形,在Rt △OHA 中,由勾股定理得:==∴AB=∴四边形ABCD 的面积=AB ×GH=故答案为:.【点睛】本题考查圆中折叠的对称性及平行四边形的证明,关键是作辅助线,本题也可通过边、角关系证出四边形ABCD 是矩形.24.2或3【解析】【分析】根据相似三角形的判定与性质,当若点A ,P ,D 分别与点B ,C ,P 对应,与若点A ,P ,D 分别与点B ,P ,C 对应,分别分析得出AP 的长度即可.【详解】解:设AP =xcm .则解析:2或3【解析】【分析】根据相似三角形的判定与性质,当若点A ,P ,D 分别与点B ,C ,P 对应,与若点A ,P ,D 分别与点B ,P ,C 对应,分别分析得出AP 的长度即可.【详解】解:设AP =xcm .则BP =AB ﹣AP =(5﹣x )cm以A ,D ,P 为顶点的三角形与以B ,C ,P 为顶点的三角形相似,①当AD :PB =PA :BC 时,352x x =-, 解得x =2或3.②当AD :BC =PA +PB 时,3=25x x-,解得x =3, ∴当A ,D ,P 为顶点的三角形与以B ,C ,P 为顶点的三角形相似,AP 的值为2或3. 故答案为2或3.【点睛】本题考查了相似三角形的问题,掌握相似三角形的性质以及判定定理是解题的关键.三、解答题25.(1)DE与⊙O相切;理由见解析;(2)4.【解析】【分析】(1)连接OD,由D为AC的中点,得到AD CD=,进而得到AD=CD,根据平行线的性质得到∠DOA=∠ODE=90°,求得OD⊥DE,于是得到结论;(2)连接BD,根据四边形对角互补得到∠DAB=∠DCE,由AD CD=得到∠DAC=∠DCA =45°,求得△ABD∽△CDE,根据相似三角形的性质即可得到结论.【详解】(1)解:DE与⊙O相切证:连接OD,在⊙O中∵D为AC的中点∴AD CD=∴AD=DC∵AD=DC,点O是AC的中点∴OD⊥AC∴∠DOA=∠DOC=90°∵DE∥AC∴∠DOA=∠ODE=90°∵∠ODE=90°∴OD⊥DE∵OD⊥DE,DE经过半径OD的外端点D∴DE与⊙O相切.(2)解:连接BD∵四边形ABCD是⊙O的内接四边形∴∠DAB+∠DCB=180°又∵∠DCE+∠DCB=180°∴∠DAB=∠DCE∵AC为⊙O的直径,点D、B在⊙O上,∴∠ADC=∠ABC=90°∵AD CD=,∴∠ABD=∠CBD=45°∵AD=DC,∠ADC=90°∴∠DAC=∠DCA=45°∵DE∥AC∴∠DCA=∠CDE=45°在△ABD和△CDE中∵∠DAB=∠DCE,∠ABD=∠CDE=45°∴△ABD∽△CDE∴ABCD=ADCE∴6CD=163AD∴AD=DC=42, CE=163,AB=6,在Rt△ADC中,∠ADC=90°,AD=DC=42,∴AC=22AD DC+=8∴⊙O的半径为4.【点睛】本题考查了直线与圆的位置关系,等腰直角三角形的性质,圆周角定理,相似三角形的判定和性质,正确的识别图形是解题的关键.26.(1)证明见解析;(2)513;(3)53、5、155(345)-【解析】【分析】(1)利用同角的余角相等,证明∠CEF=∠AFB,即可解决问题;(2)过点F作FG⊥DC交DC与点G,交AB于点H,由△FGE∽△AHF得出AH=5GF,再利用勾股定理求解即可;(3)分①当∠EFC=90°时; ②当∠ECF=90°时;③当∠CEF=90°时三种情况讨论解答即可.【详解】(1)解:在矩形ABCD中,∠B=∠C=∠D=90°由折叠可得:∠D=∠EFA=90°∵∠EFA=∠C=90°∴∠CEF+∠CFE=∠CFE+∠AFB=90°∴∠CEF=∠AFB在△ABF和△FCE中∵∠AFB=∠CEF,∠B=∠C=90°△ABF∽△FCE(2)解:过点F作FG⊥DC交DC与点G,交AB于点H,则∠EGF=∠AHF=90°在矩形ABCD中,∠D=90°由折叠可得:∠D=∠EFA=90°,DE=EF=1,AD=AF=5∵∠EGF=∠EFA=90°∴∠GEF+∠GFE=∠AFH+∠GFE=90°∴∠GEF=∠AFH在△FGE和△AHF中∵∠GEF=∠AFH,∠EGF=∠FHA=90°∴△FGE∽△AHF∴EFAF=GFAH∴15=GFAH∴AH=5GF在Rt△AHF中,∠AHF=90°∵AH2+FH2=AF2∴(5 GF)2+(5-GF)2=52∴GF=5 13∴△EFC的面积为12×513×2=513;(3)解:①当∠EFC=90°时,A 、F 、C 共线,如图所示:设DE=EF=x,则CE=3-x, ∵AC=22223534AD CD +=+=,∴CF=34-x, ∵∠CFE=∠D=90°, ∠DCA=∠DCA,∴△CEF ∽△CAD, ∴CE EF CA AD =,即534x =,解得:ED=x=5(345)-; ②当∠ECF=90°时,如图所示:∵AD=1AF =5,AB=3, ∴1BF 221AF AB -设1DE =x,则1E C =3-x,∵∠DCB=∠ABC=90°, 111CF E F AB ∠=∠∴11CE F ∽1BF A ,∴11111E C E F F B F A =,即345x x -=,解得:x=1E D =53; 由折叠可得 :222E F E D = ,设2E C x =,则2223E F DE x ==+,2549CF =+=, 在RT △22E F C 中,∵2222222CF CE E F +=,即9²+x²=(x+3)²,解得x=2E C =12, ∴231215DE =+=;③当∠CEF=90°时,AD=AF,此时四边形AFED是正方形,∴AF=AD=DE=5,综上所述,DE的长为:53、5、15、5(345).【点睛】本题考查了翻折的性质,相似三角形的判定与性质,勾股定理,掌握翻折的性质,分类探讨的思想方法是解决问题的关键.27.吊灯AB的长度约为1.1米.【解析】【分析】延长CD交AB的延长线于点E,构建直角三角形,分别在两个直角三角形△BDE和△AEC 中利用正弦和正切函数求出AE长和BE长,即可求解.【详解】解:延长CD交AB的延长线于点E,则∠AEC=90°,∵∠BDE=60°,∠DCB=30°,∴∠CBD=60°﹣30°=30°,∴∠DCB=∠CBD,∴BD=CD=6(米)在Rt△BDE中,sin∠BDE=BE BD,∴BE=BD•sin∠BDE═6×sin60°=3≈5.19(米),DE=12BD=3(米),在Rt△AEC中,tan∠ACE=AE CE,∴AE=CE•tan∠ACE=(6+3)×tan35°≈9×0.70=6.30(米),∴AB=AE﹣BE≈6.30﹣5.19≈1.1(米),∴吊灯AB的长度约为1.1米.【点睛】本题考查解直角三角形的应用,解答此题的关键是构建直角三角形,利用锐角三角函数进行解答.28.(1)①(6,23),②(3,33);(2)()()()()2434303313333523123595439xxx x xSx xx⎧+≤≤⎪⎪⎪-+-<≤⎪⎪=⎨⎪-+<≤⎪⎪⎪>⎪⎩【解析】【分析】(1)①由四边形OABC是矩形,根据矩形的性质,即可求得点B的坐标;②由正切函数,即可求得∠CAO的度数,③由三角函数的性质,即可求得点P的坐标;(2)分别从当0≤x≤3时,当3<x≤5时,当5<x≤9时,当x>9时去分析求解即可求得答案.【详解】解:(1)①∵四边形OABC是矩形,∴AB=OC,OA=BC,∵A(6,0)、C(0,23),∴点B的坐标为:(6,23);②如图1:当点Q与点A重合时,过点P作PE⊥OA于E,∵∠PQO=60°,D(0,3∴3∴AE=3tan60PE=,∴OE=OA-AE=6-3=3, ∴点P 的坐标为(3,33);故答案为:①(6,23),②(3,33); (2)①当0≤x ≤3时,如图,OI =x ,IQ =PI •tan 60°=3,OQ =OI +IQ =3+x ;由题意可知直线l ∥BC ∥OA , ∴31333EF PE DC OQ PO DO ====, ∴EF =133+x () 此时重叠部分是梯形,其面积为:S 梯形=12(EF +OQ )•OC =43(3+x ) ∴4343x S =+. 当3<x ≤5时,如图AQ =OI +IO -OA =x +3-6=x -3AH 3x -3)S=S 梯形﹣S △HAQ =S 梯形﹣12AH •AQ 433+x 23x (-3) ∴231333S x x =+ ③当5<x ≤9时,如图∵CE ∥DP ∴CO CE DO DP = ∴2333CE x= ∴23CE x = 263BE x =- S=12(BE +OA )•OC =3(12﹣23x ) ∴23123S x =-+. ④当x >9时,如图∵AH ∥PI∴AO AH OI PI = ∴633x =∴183AH =S=12543.综上:24343033313333523123595439xxx x xSx xx⎧+≤≤⎪⎪⎪-+-<≤⎪⎪=⎨⎪-+<≤⎪⎪⎪>⎪⎩()()()().【点睛】此题考查了矩形的性质,相似三角形的判定与性质、等腰三角形的性质以及直角三角形的性质等知识.此题综合性较强,难度较大,注意数形结合思想与分类讨论思想的应用.29.(1)2s(2)①证明见解析,②33√【解析】试题分析:(1)由当点B于点O重合的时候,BO=OD+BD=4cm,又由三角板以2cm/s的速度向右移动,即可求得三角板运动的时间;(2)①连接OF,由AC与半圆相切于点F,易得OF⊥AC,然后由∠ACB=90°,易得OF∥CE,继而证得EF平分∠AEC;②由△AFO是直角三角形,∠BAC=30°,OF=OD=3cm,可求得AF的长,由EF平分∠AEC,易证得△AFE是等腰三角形,且AF=EF,则可求得答案.试题解析:(1)∵当点B于点O重合的时候,BO=OD+BD=4cm,∴t=42=2(s);∴三角板运动的时间为:2s;(2)①证明:连接O与切点F,则OF⊥AC,∵∠ACE=90°,∴EC⊥AC,∴OF∥CE,∴∠OFE=∠CEF,∵OF=OE,∴∠OFE=∠OEF,∴∠OEF=∠CEF,即EF平分∠AEC;②由①知:OF⊥AC,∴△AFO是直角三角形,∵∠BAC=30°,OF=OD=3cm,∴tan30°=3AF,∴AF=33cm,由①知:EF平分∠AEC,∴∠AEF=∠CEF=12∠AEC=30°,∴∠AEF=∠EAF,∴△AFE是等腰三角形,且AF=EF,∴EF=33cm.30.(1)DE与⊙O相切;理由见解析;(2)4.【解析】【分析】(1)连接OD,由D为AC的中点,得到AD CD=,进而得到AD=CD,根据平行线的性质得到∠DOA=∠ODE=90°,求得OD⊥DE,于是得到结论;(2)连接BD,根据四边形对角互补得到∠DAB=∠DCE,由AD CD=得到∠DAC=∠DCA =45°,求得△ABD∽△CDE,根据相似三角形的性质即可得到结论.【详解】(1)解:DE与⊙O相切证:连接OD,在⊙O中∵D为AC的中点∴AD CD=∴AD=DC∵AD=DC,点O是AC的中点∴OD⊥AC∴∠DOA=∠DOC=90°∵DE∥AC∴∠DOA=∠ODE=90°∵∠ODE=90°∴OD⊥DE∵OD⊥DE,DE经过半径OD的外端点D∴DE与⊙O相切.(2)解:连接BD∵四边形ABCD是⊙O的内接四边形∴∠DAB+∠DCB=180°又∵∠DCE+∠DCB=180°∴∠DAB=∠DCE∵AC为⊙O的直径,点D、B在⊙O上,∴∠ADC=∠ABC=90°∵AD CD=,∴∠ABD=∠CBD=45°∵AD=DC,∠ADC=90°∴∠DAC=∠DCA=45°∵DE∥AC∴∠DCA=∠CDE=45°在△ABD和△CDE中∵∠DAB=∠DCE,∠ABD=∠CDE=45°∴△ABD∽△CDE∴ABCD=ADCE∴6CD=163AD∴AD=DC=42, CE=163,AB=6,在Rt△ADC中,∠ADC=90°,AD=DC=42,∴AC=22AD DC+=8∴⊙O的半径为4.【点睛】本题考查了直线与圆的位置关系,等腰直角三角形的性质,圆周角定理,相似三角形的判定和性质,正确的识别图形是解题的关键.31.(1)y =x 2+2x ﹣3;(2)存在,点P 坐标为⎝⎭或⎝⎭;(3)点N 的坐标为(﹣4,1) 【解析】【分析】(1)分别令y =0 ,x =0,可表示出A 、B 、C 的坐标,从而表示△ABC 的面积,求出a 的值继而即可得二次函数解析式;(2)如图①,当点P 在x 轴上方抛物线上时,平移BC 所在的直线过点O 交x 轴上方抛物线于点P ,则有BC ∥OP ,此时∠POB =∠CBO ,联立抛物线得解析式和OP 所在直线的解析式解方程组即可求解;当点P 在x 轴下方时,取BC 的中点D ,易知D 点坐标为(12,32-),连接OD 并延长交x 轴下方的抛物线于点P ,由直角三角形斜边中线定理可知,OD =BD ,∠DOB =∠CBO 即∠POB =∠CBO ,联立抛物线的解析式和OP 所在直线的解析式解方程组即可求解.(3)如图②,通过点M 到x 轴的距离可表示△ABM 的面积,由S △ABM =S △BNM ,可证明点A 、点N 到直线BM 的距离相等,即AN ∥BM ,通过角的转化得到AM =BN ,设点N 的坐标,表示出BN 的距离可求出点N .【详解】(1)当y =0时,x 2﹣(a +1)x +a =0,解得x 1=1,x 2=a ,当x =0,y =a∴点C 坐标为(0,a ),∵C (0,a )在x 轴下方∴a <0∵点A 位于点B 的左侧,∴点A 坐标为(a ,0),点B 坐标为(1,0),∴AB =1﹣a ,OC =﹣a ,∵△ABC 的面积为6, ∴()()1162a a --=, ∴a 1=﹣3,a 2=4(因为a <0,故舍去),∴a =﹣3,∴y =x 2+2x ﹣3;(2)设直线BC :y =kx ﹣3,则0=k ﹣3,∴k =3;①当点P 在x 轴上方时,直线OP 的函数表达式为y =3x ,。
湘教版九年级2018--2019学年度第一学期期末考试数学试卷

试卷第1页,总9页绝密★启用前 湘教版九年级2018--2019学年度第一学期期末考试 数学试卷 分望你做题时,不要慌张,要平心静气,把字写得工整些,让自己和老师都看得舒服些,祝你成功!一、单选题(计40分) 1.(本题4分)方程)3(3-=-x x x 的解为( ) A .0=x B .01=x ,32=x C .3=x D .11=x ,32=x 2.(本题4分)如图所示的支架(一种小零件)的两个台阶的高度和宽度相等,则它的左视图为( ) A . B . C . D . 3.(本题4分)在学校乒乓球比赛中,从陈亮、李明、刘松、周杰、王刚这五人中,随机抽签一组对手,正好抽到王刚与刘松的概率是( ) A .15 B .16 C .110 D .14 4.(本题4分)某企业2018年初获利润300万元,到2020年初计划利润达到507万元.设这两年的年利润平均增长率为x .应列方程是( ) A . 300(1+x )=507 B . 300(1+x )2=507 C . 300(1+x )+300(1+x )2=507 D . 300+300(1+x )+300(1+x )2=507 5.(本题4分)等腰三角形边长分别为a ,b ,2,且a ,b 是关于x 的一元二次方程试卷第2页,总9页 x 2﹣6x+n ﹣1=0的两根,则n 的值为 ( ) A . 9 B . 10 C . 9或10 D . 8或10 6.(本题4分)若反比例函数y=x k 3 的图象经过点(2,3),则k 的值是 ( ) A . 6 B . ﹣6 C . 3 D . ﹣3 7.(本题4分)数学活动课,老师和同学一起去测量校内某处的大树AB 的高度,如图,老师测得大树前斜坡DE 的坡度i=1:4,一学生站在离斜坡顶端E 的水平距离DF 为8m 处的D 点,测得大树顶端A 的仰角为α,已知sin α=53,BE=1.6m ,此学生身高CD=1.6m ,则大树高度AB 为( )m .A . 7.4B . 7.2C . 7D . 6.88.(本题4分)如图,线段AB 两个端点的坐标分别为A (2,2)、B (3,1),以原点O 为位似中心,在第一象限内将线段AB 扩大为原来的2倍后得到线段CD ,则端点C 的坐标分别为( )A . (3,1)B . (3,3)C . (4,4)D . (4,1)9.(本题4分)如图,⊙O 的直径AB 垂直于弦CD ,垂足是E ,∠A=22.5°,OC=8,则CD 的长为( )A . 42B . 8 2C . 8D . 1610.(本题4分)已知二次函数y=ax 2+bx+c (a≠0)的图象如图,在下列代数式中试卷第3页,总9页 (1)a+b+c >0;(2)﹣4a <b <﹣2a (3)abc >0;(4)5a ﹣b+2c <0; 其中正确的个数为( ) A . 1个 B . 2个 C . 3个 D . 4个二、填空题(计20分) 11.(本题5分)将抛物线向右平移个单位,再向下平移个单位后所得到新抛物线的解析式是________,顶点坐标是________. 12.(本题5分)如图,四边形OABC 为菱形,点B 、C 在以点O 为圆心的上,若OA =1cm ,∠1=∠2,则的长为 cm . 13.(本题5分)两个相似多边形对应边的比为,小多边形的面积为,那么大多边形的面积为________. 14.(本题5分)如图,在一笔直的海岸线l 上有A 、B 两个观测站,AB=2km ,从A 测得船C 在北偏东45°的方向,从B 测得船C 在北偏东22.5°的方向,则船C 离海岸线l 的距离(即CD 的长)为_____km (精确到0.1).试卷第4页,总9页 三、解答题(计90分) 15.(本题8分)解下列方程: (1)x 2+6x+5=0; (2)2(x ﹣1)2=3x ﹣3;16.(本题8分)一条单车道的抛物线形隧道如图所示.隧道中公路的宽度,隧道的最高点到公路的距离为.建立适当的平面直角坐标系,求抛物线的表达式;现有一辆货车的高度是,货车的宽度是,为了保证安全,车顶距离隧道顶部至少,通过计算说明这辆货车能否安全通过这条隧道.试卷第5页,总9页 17.(本题8分)如图所示,反比例函数y =k x的图象经过点A(2,3). (1)求这个函数的表达式; (2)请你判断,B(1,6)是否在这个反比例函数的图象上,并说明理由. 18.(本题8分)国务院办公厅在2015年3月16日发布了《中国足球发展改革总统方案》,一年过去了,为了了解足球知识的普及情况,某校举行“足球在身边”的专题调查活动,采取随机抽样的方法进行问卷调查,调查结果划分为“非常了解”、“比较了解”、“基本了解”、“不太了解”四个等级,并将调查结果绘制成两幅不完整的统计图(如图),请根据图中提供的信息,解答下列问题: (1)被调查的学生共有 人. (2)在扇形统计图中,表示“比较了解”的扇形的圆心角度数为 度; (3)从该校随机抽取一名学生,抽中的学生对足球知识是“基本了解”的概率的是多少?试卷第6页,总9页19.(本题10分)为预防“手足口病”,某校对教室进行“药熏消毒”.已知药物燃烧阶段,室内每立方米空气中的含药量y (mg )与燃烧时间x (分钟)成正比例;燃烧后,y 与x 成反比例(如图所示).现测得药物10分钟燃完,此时教室内每立方米空气含药量为8mg .据以上信息解答下列问题:(1)从消毒开始,经多长时间,教室内每立方米空气含药量为4mg .(2)当每立方米空气中含药量低于1.6mg 时,对人体方能无毒害作用,那么从消毒开试卷第7页,总9页 始,经多长时间学生才可以回教室?20.(本题10分)如图所示,学校准备在教师周转房旁边搭建一个简易矩形摩托车车棚,一边利用教学楼的后墙(可利用的墙长为19m ),另外三边利用学校现有总长38m 的铁栏围成. (1)若围成的面积为180m 2,试求出摩托车车棚的长和宽; (2)能围成的面积为200m 2摩托车车棚吗?如果能,请你给出设计方案;如果不能,请说明理由.试卷第8页,总9页21.(本题12分)如图,点D 、E 分别在AB 、AC 边上,且AD=5,BD=3,AE=4,CE=6. 试说明:(1)△ADE ∽△ACB ;(2)若BC=9,求DE 的长.22.(本题12分)如图,海中有一小岛P ,在距小岛P 的海里范围内有暗礁,一轮船自西向东航行,它在A 处时测得小岛P 位于北偏东60°,且A 、P 之间的距离为32海里,若轮船继续向正东方向航行,轮船有无触礁危险?请通过计算加以说明.如果有危险,轮船自A 处开始至少沿东偏南多少度方向航行,才能安全通过这一海域?试卷第9页,总9页 23.(本题14分)如图,在Rt △ABC 中∠ABC=90°,AC 的垂直平分线交BC 于D 点,交AC 于E 点,OC=OD . (1)若,DC=4,求AB 的长; (2)连接BE ,若BE 是△DEC 的外接圆的切线,求∠C 的度数.参考答案1.D【解析】试题分析:本题首先进行移项,然后利用因式分解法进行求解.移项得:(x -3)-x (x -3)=0,因式分解可得:(x -3)(1-x )=0,解得:121,3x x ==.考点:解一元二次方程2.D【解析】【分析】找到从左面看所得到的图形即可,注意所有的看到的棱都应表现在视图中.【详解】从左面看去,是两个有公共边的矩形,如图所示:故选D .【点睛】本题考查了三视图的知识,左视图是从物体的左面看得到的视图.视图中每一个闭合的线框都表示物体上的一个平面,而相连的两个闭合线框常不在一个平面上.3.C【解析】试题分析:画树状图得:∵共有20种等可能的结果,正好抽到王刚与刘松的有2种情况, ∴正好抽到王刚与刘松的概率是:212010.故选C .考点:列表法与树状图法求概率4.B【解析】【分析】根据年利润平均增长率,列出变化增长前后的关系方程式进行求解.【详解】设这两年的年利润平均增长率为x,列方程为:300(1+x)2=507故选:B.【点睛】本题考查了由实际问题抽象出一元二次方程,解题的关键是怎么利用年利润平均增长率列式计算.5.B【解析】试题解析:∵三角形是等腰三角形,∴①a=2,或b=2,②a=b两种情况,①当a=2,或b=2时,∵a,b是关于x的一元二次方程x2-6x+n-1=0的两根,∴x=2,把x=2代入x2-6x+n-1=0得,22-6×2+n-1=0,解得:n=9,当n=9,方程的两根是2和4,而2,4,2不能组成三角形,故n=9不合题意,②当a=b时,方程x2-6x+n-1=0有两个相等的实数根,∴△=(-6)2-4(n-1)=0解得:n=10,故选B.考点:1.根的判别式;2.一元二次方程的解;3.等腰直角三角形.6.C【解析】【分析】把(2,3)代入y=即可求出k的值.【详解】把(2,3)代入y=得,3=,∴k=3.故选C.【点睛】本题考查了反比例函数的图像与性质,反比例函数图像上点的横纵坐标满足反比例函数解析式.7.D【解析】如图所示:过点C作延长线于点G,交EF于点N,根据题意可得:,计算得出:,,,,,设,则,故,即,计算得出:,故,则,故选D.8.C【解析】【分析】利用位似图形的性质结合对应点坐标与位似比的关系得出C点坐标.【详解】∵以原点O为位似中心,在第一象限内将线段AB扩大为原来的2倍后得到线段CD,∴A点与C点是对应点,∵C点的对应点A的坐标为(2,2),位似比为:1:2,∴点C的坐标为:(4,4)故选:C.【点睛】本题主要考查位似变换,坐标与图形性质,关键在于找到相似比即可解答.9.B【解析】【分析】根据圆周角定理得∠BOC=2∠A=45°,由于O的直径AB垂直于弦CD,根据垂径定理得CE=DE,且可判断△OCE为等腰直角三角形,所以然后利用CD=2CE进行计算.【详解】∵∴∵O的直径AB垂直于弦CD,∴CE=DE,△OCE为等腰直角三角形,∴∴故选:B.【点睛】考查垂径定理,等腰直角三角形,圆周角定理,综合性比较强,注意垂径定理的应用. 10.A【解析】【分析】由抛物线开口向上得到a大于0,再由对称轴在y轴右侧得到a与b异号,即b小于0,由抛物线与y轴交于正半轴,得到c大于0,可得出abc的符合,对于(3)作出判断;由x=1时对应的函数值小于0,将x=1代入二次函数解析式得到a+b+c小于0,(1)错误;根据对称轴在1和2之间,利用对称轴公式列出不等式,由a大于0,得到-2a小于0,在不等式两边同时乘以-2a,不等号方向改变,可得出不等式,对(2)作出判断;由x=-1时对应的函数值大于0,将x=-1代入二次函数解析式得到a-b+c大于0,又4a大于0,c大于0,可得出a-b+c+4a+c大于0,合并后得到(4)正确,综上,即可得到正确的个数.【详解】由图形可知:抛物线开口向上,与y轴交点在正半轴,∴a>0,b<0,c>0,即abc<0,故(3)错误;又x=1时,对应的函数值小于0,故将x=1代入得:a+b+c<0,故(1)错误;∵对称轴在1和2之间,∴又a>0,∴在不等式左右两边都乘以−2a得:−2a>b>−4a,故(2)正确;又x=−1时,对应的函数值大于0,故将x=1代入得:a−b+c>0,又a>0,即4a>0,c>0,∴5a−b+2c=(a−b+c)+4a+c>0,故(4)错误,综上,正确的有1个,为选项(2).故选:A.【点睛】考查二次函数图象与系数的关系,掌握二次函数系数对图象的影响是解题的关键.11.【解析】【分析】根据“上加下减,左加右减”的原则写出平移后抛物线的解析式,然后根据解析式写出顶点坐标.【详解】将抛物线y=−2x2+1向右平移1个单位,再向下平移3个单位后所得到新抛物线的解析式是y=−2(x−1)2−2,其顶点坐标为:(1,−2).故答案是:y=−2(x−1)2−2;(1,−2).【点睛】主要考查的是函数图象的平移,用平移规律“左加右减,上加下减”直接代入函数解析式求得平移后的函数解析式.12.【解析】试题分析:连接OB,菱形的性质得出OA∥BC,OC=BC,求出∠AOC+∠OCB=180°,OC=BC=OB,根据等边三角形的判定得出△OCB是等边三角形,求出∠OCB=60°,求出∠AOC=120°,求出∠FOE=120°,OF=1cm,代入公式求出即可.解:连接OB,则OC=OB,∵四边形OABC为菱形,∴OA∥BC,OC=BC,∴∠AOC+∠OCB=180°,OC=BC=OB,∴△OCB是等边三角形,∴∠OCB=60°,∴∠AOC=180°﹣60°=120°,∵∠1=∠2,∴∠FOE=∠COE+∠1=∠COE+∠2=∠AOC=120°,∵OA=OC=OF=1cm,∴的长为=cm,故答案为:.考点:菱形的性质;弧长的计算.13.72【解析】【分析】根据相似多边形对应边之比、周长之比等于相似比,而面积之比等于相似比的平方计算.【详解】两个相似的七边形的相似比为3:2,面积的比是9:4,因而可以设较小的七边形的面积是4xcm2,则较大的多边形的面积是9xcm2,根据小多边形的面积为32cm2,就得到4x=32解得x=8因而大多边形的面积是9x=72cm2.【点睛】本题考查相似多边形的性质.14.3.4.【解析】分析:根据题意在CD上取一点E,使BD=DE,设BD=DE=x,则由AD与CD的关系和勾股定理可求得x,从而可求得CD的长.详解:在CD上取一点E,使BD=DE,设BD=DE=x.∵BD=DE,∴∠EBD=45°,由题意可得∠CAD=45°,∴AD=DC,∵从B测得船C在北偏东22.5°的方向,∴∠BCE=∠CBE=22.5°,∴BE=EC,∵AB=AD﹣BD=2km,∴EC=BE=DC﹣DE=2km,∵BD=DE=x,∴CE=BE=x,∴2+x=x+x,解得x=.∴DC=(2+)≈3.4(km)故答案为3.4.点睛:此题主要考查了解直角三角形的应用,得出BE=EC=2是解题关键.15.(1)x1=-1,x2=-5;(2)x1=1,x2=2.5【解析】【分析】(1)因为二次项系数为1,所以利用配方法求解即可求得答案;(2)原式可变为2(x−1)2=3(x−1),然后提取公因式,可得(x−1)(2x−2−3)=0,继而求得答案.【详解】(1)x2+6x+5=0,x2+6x=-5,x2+6x+9=-5+9,(x+3)2=4,解得:x+3=±2,x1=-1,x2=-5;(2)2(x−1)2=3x−3,2(x−1)2=3(x−1),∴(x−1)(2x−2−3)=0,∴x−1=0,2x−2−3=0,∴x1=1,x2=2.5.【点睛】此题考查了一元二次方程的解法.此题比较简单,注意选择适宜的解题方法是解此题的关键.16.能安全通过这条隧道【解析】【分析】(1)以AB所在直线为x轴,以抛物线的对称轴为y轴建立平面直角坐标系xOy,如图所示,利用待定系数法即可解决问题.(1)求出x=1时的y的值,与4.4+0.5比较即可解决问题.【详解】本题答案不唯一,如:以所在直线为轴,以抛物线的对称轴为轴建立平面直角坐标系,如图所示.∴,,. 设这条抛物线的表达式为. ∵抛物线经过点, ∴. ∴ ∴抛物线的表达式为,.当时,, ∵,∴这辆货车能安全通过这条隧道.【点睛】本题考查的是二次函数的实际应用,熟练掌握二次函数的性质是解题的关键.17.(1)y=6x(2)点B(1,6)在这个反比例函数的图象上 【解析】试题分析:(1)先把A 点的坐标代入反比例函数k y x =中,求出k ,即可求出函数解析式;(2)再把B 点的横坐标代入反比例函数的解析式,可求出y ,若y 的值与B 点的纵坐标相等,则说明B 在函数的图象上,否则就不在函数图象上.试题解析:(1)把(2,3)代入k y x =中得 3=2k , ∴k=6, ∴函数的解析式是y=6x;(2)把x=1代入y=6x中得y=6, ∴点B 在此函数的图象上.考点:1.待定系数法求反比例函数解析式;2.反比例函数图象上点的坐标特征.18.(1)300;(2)108;(3)0.4.【解析】试题分析:(1)根据统计图中的数据可以求得本次调查的人数;(2)根据条形统计图中的数据可以求得在扇形统计图中,表示“比较了解”的扇形的圆心角度数;(3)根据统计图中的数据可以求得从该校随机抽取一名学生,抽中的学生对足球知识是“基本了解”的概率.试题解析:(1)由题意可得,被调查的学生有:60÷20%=300(人),故答案为:300;(2)在扇形统计图中,表示“比较了解”的扇形的圆心角度数为:360°×90300=108°,故答案为:108;(3)由题意可得,从该校随机抽取一名学生,抽中的学生对足球知识是“基本了解”的概率是:300609030300---=0.4,即从该校随机抽取一名学生,抽中的学生对足球知识是“基本了解”的概率是0.4.考点:概率公式;扇形统计图;条形统计图;统计与概率.19.(1)从消毒开始,经5分钟和20分钟,教室内每立方米空气含药量为4mg ;(2)从消毒开始经过50分钟学生才可返回教室.【解析】【分析】(1)首先根据题意,药物燃烧阶段,室内每立方米空气中的含药量y 与燃烧时间x 成正比例;燃烧后,y 与x 成反比例,且其图象都过点(10,8),将数据代入用待定系数法可得反比例函数的关系式,分别求出函数解析式,再计算出y=4时,x 的值即可;(2)根据题意可知得<1.6,解不等式即可.【详解】 (1)设药物燃烧阶段函数解析式为y=k 1x (k 1≠0),由题意得:8=10k 1,∴k1=,∴此阶段函数解析式为y=x(0≤x≤10).当y=4时,x=5;设药物燃烧结束后函数解析式为y=(k2≠0),由题意得:=8,∴k2=80,∴此阶段函数解析式为y=(x≥10).,当y=4时,x=20,答:从消毒开始,经5分钟和20分钟,教室内每立方米空气含药量为4m g;(2)当y<1.6时,得<1.6,∵x>0,∴1.6x>80,解得x>50.答:从消毒开始经过50分钟学生才可返回教室.【点睛】本题主要考查了一次函数、反比例函数的应用,解答该类问题的关键是确定两个变量之间的函数关系,然后利用待定系数法求出它们的关系式.20.摩托车棚长19m,宽10m.【解析】【分析】(1)利用长方形的周长表示出各边长,即可表示出矩形面积,求出即可;(2)利用长方形的面积列方程,利用根的判别式解答即可.【详解】(1)设AB=x,则BC=38−2x;根据题意列方程的,x(38−2x)=180,解得x1=10,x2=9;当x=10,38−2x=18(米),当x=9,38−2x=20(米),而墙长19m,不合题意舍去,答:若围成的面积为180m2,自行车车棚的长和宽分别为10米,18米;(2)根据题意列方程的,x(38−2x)=200,整理得出:x2−19x+100=0;△=b2−4ac=361−400=−39<0,故此方程没有实数根,答:因此如果墙长19m,满足条件的花园面积不能达到200m2.【点睛】考查一元二次方程的应用,读懂题目,设出未知数,根据题目中的等量关系列出方程是解题的关键.21.(1)证明见解析;(2)DE=4.5【解析】【分析】(1)由条件可得,且为公共角,则可证明;(2)由(1)可得,可求得.【详解】⑴∵AD=5,BD=3,AE=4,CE=6,∴AB=8,AC=10,∴,∵∠A=∠A,∴△ADE∽△ACB;⑵∵△ADE∽△ACB,∴,∵BC=9,∴DE=4.5.【点睛】本题主要考查相似三角形的判定和性质,掌握三角形相似的判定方法,即有两组角对应相等、两组对应边的比相等且夹角相等或三组对应边的比相等是解题的关键.22.轮船自A处开始至少沿南偏东75°度方向航行,才能安全通过这一海域.【解析】试题分析:过P作PB⊥AM于B,则PC的长是A沿AM方向距离P点的最短距离,求出P C 长和16比较即可,第二问设出航行方向,利用特殊角的三角函数值确定答案.试题解析:过P作PB⊥AM于B,在Rt△APB中,∵∠PAB=30°,∴PB=AP=×32=16海里,∵16<16故轮船有触礁危险,为了安全,应该变航行方向,并且保证点P到航线的距离不小于暗礁的半径16海里,即这个距离至少为16海里,设安全航向为AC,作PD⊥AC于点D,由题意得,AP=32海里,PD=16海里,∵sin∠PAC=,∴在Rt△PAD中,∠PAC=45°,∴∠BAC=∠PAC-∠PAB=45°-30°=15°,答:轮船自A处开始至少沿东偏南15°度方向航行,才能安全通过这一海域.23.(1);(2)30°【解析】【分析】(1)由于DE垂直平分AC,那么AE=EC,∠DEC=90°,而∠ABC=∠DEC=90°,∠C=∠C,易证,△ABC∽△DEC,∠A=∠CDE,于是sin∠CDE=sinA=,AB:AC=DE:DC,而DC=4,易求EC,利用勾股定理可求DE,易知AC=6,利用相似三角形中的比例线段可求AB;(2)连接OE,由于∠DEC=90°,那么∠EDC+∠C=90°,又BE是切线,那么∠BEO=90°,于是∠EOB+∠EBC=90°,而BE是直角三角形斜边上的中线,那么BE=CE,于是∠EBC=∠C,从而有∠EOB=∠EDC,又OE=OD,易证△DEO是等边三角形,那么∠EDC=60°,从而可求∠C.【详解】解:(1)∵AC的垂直平分线交BC于D点,交AC于E点,∴∠DEC=90°,AE=EC,∵∠ABC=90°,∠C=∠C,∴∠A=∠CDE,△ABC∽△DEC,∴sin∠CDE=,AB:AC=DE:DC,∵DC=4,∴ED=3,∴DE=,∴AC=6,∴AB:6=:4,∴AB=;(2)连接OE,∵∠DEC=90°,∴∠EDC+∠C=90°,∵BE是⊙O的切线,∴∠BEO=90°,∴∠EOB+∠EBC=90°,∵E是AC的中点,∠ABC=90°,∴BE=EC,∴∠EBC=∠C,∴∠EOB=∠EDC,又∵OE=OD,∴△DOE是等边三角形,∴∠EDC=60°,∴∠C=30°.【点睛】考查了切线的性质、线段垂直平分线的性质、相似三角形的判定和性质、勾股定理、等边三角形的判定和性质.解题的关键是连接OE,构造直角三角形.。
株洲市芦淞区九年级上学期化学期末考试试卷

株洲市芦淞区九年级上学期化学期末考试试卷姓名:________ 班级:________ 成绩:________一、单选题 (共15题;共30分)1. (2分)(2018·门头沟模拟) 如图是大型成就展中的“碳足迹计算器模型”。
倡导“低碳”生活,应从生活中的点滴做起。
下列做法不符合“低碳”理念的是_________。
A . 外出随手关灯B . 双面使用纸张C . 骑自行车出行D . 丢弃未喝完的矿泉水瓶2. (2分)(2017·泰兴模拟) 下列物质的用途中,主要利用其物理性质的是()A . 稀盐酸用来制药物B . 干冰用于人工降雨C . 铁粉用作食品保鲜吸氧剂D . 酒精用作燃料3. (2分)(2018·海南模拟) 学习化学的一个重要途径是科学探究,实验是科学探究的重要手段,下列化学实验操作正确的是()A . 滴加液体B . 验满氧气C . 读取液体体积D . 向试管中加固体4. (2分) (2015九上·湖南期中) 吸烟有害健康.在公共场所,非吸烟者会因少数吸烟者吸烟造成被动吸烟,这是因为()A . 分子很小B . 分子之间有间隙C . 分子在不断运动D . 分子是可分的5. (2分)(2018·乌鲁木齐) 学习化学以后,我们对水有了更全面的认识。
下列说法错误的是()A . 在自来水厂净化水的过程中,发生的变化都是物理变化B . 煮沸可以降低水的硬度C . 水是一种氧化物D . 电解水时在负极得到氢气6. (2分) (2017九上·海淀期中) 下列物质的化学式书写不正确的是()A . 氧气O2B . 二氧化硫SO2C . 氧化铁FeOD . 氯化钠NaCl7. (2分)(2014·桂林) 下列物质与用途的对应关系错误的是()A . 食盐﹣﹣调味品B . 干冰﹣﹣制冷剂C . 明矾﹣﹣净水剂D . 石墨﹣﹣切割玻璃8. (2分)(2013·贵港) 有关物质的检验、鉴别、除杂,下列说法正确的是()A . 把燃着的木条伸入某集气瓶内,木条熄灭,说明瓶内的气体是CO2B . 用点燃的方法除去CO2中少有的COC . 不用另加试剂就可以把MgSO4、KOH、HCl、BaCl2四种溶液鉴别出来D . 向某溶液中加入BaCl2溶液,产生白色沉淀,过滤后沉淀中加入足量的稀硝酸,沉淀部分溶解并产生气泡,说明溶液中可能含有硫酸根离子9. (2分)近几年我国一些地区时有火灾发生.如果室内遭遇火灾时,下列自救措施不正确的是()A . 尽快到达最近的可用出口的楼梯B . 可将毛巾用水浸湿,捂在口鼻上作防毒面具C . 遇房内浓烟弥漫时,可匍匐爬行逃生D . 躲在衣柜内等待救援10. (2分)(2017·潮阳模拟) 如图,海水淡化可采用膜分离技术,对淡化膜右侧的海水加压,水分子可以透过淡化膜进入左侧淡水池,而海水中的各离子不能通过淡化膜,从而得到淡水.对加压后右侧海水成分变化进行分析,正确的是()A . 溶质质量增加B . 溶剂质量减少C . 溶液质量不变D . 溶质质量分数减少11. (2分)下列措施有不利于改善环境质量的是()A . 将废电池深埋,以减少重金属的污染B . 向煤中加入石灰石作为脱硫剂,可以减少SO2的排放C . 利用太阳能、潮汐能、风力发电,以获取清洁能源D . 利用二氧化碳等原料合成聚碳酸酯类可降解塑料12. (2分) (2020九上·新泰期末) 下列验证Zn、Cu、Ag三种金属活动性顺序的试剂不正确的一组是()A . Zn(NO3)2溶液、Cu、AgNO3溶液B . Zn、Ag、CuSO4溶液C . Zn、Cu、H2SO4、AgNO3溶液D . Zn、Cu、AgNO3溶液13. (2分)(2017·永州) 化学在环境保护、资源核能源利用等方面起着重要的作用.下列说法不正确的是()A . 涂油和刷油漆能防止钢铁生锈B . 使用可降解塑料可以减少“白色污染”C . PM2.5专用口罩中使用了活性炭,是利用了活性炭的吸附性D . 目前计入空气污染指数的有害气体主要包括:SO2、CO、NO2、O2等14. (2分)人们常用形象的图式来描述物质世界例如:水的电解可表示为:可见,化学反应前后,下列各项中可能有变化的是()A . 原子的数目B . 分子的数目C . 原子的种类D . 分子的种类15. (2分)(2018·花都模拟) 除去下列各物质中混有少量杂质,所用试剂正确的是()选项物质杂质所用试剂A镁粉铁粉稀硫酸B N2O2灼热的铜网C稀盐酸MgCl2KOH溶液D NaCl Na2SO4Ba(NO3)2溶液A . AB . BC . CD . D二、填空题 (共4题;共17分)16. (5分)(2018·丹东模拟) 用化学用语填空:(1)相对分子质量最小且可燃的有机物________(2)严重干旱地区可用于人工降雨的是________(3)制作糕点用的发酵粉主要成分之一________(4)溶于水后能形成酸雨的大气污染物________17. (4分) (2018九上·双城期中) 碳及碳的化合物在人类生产生活中应用广泛,随着科技的发展,含碳元素的新材料不断涌现。
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株洲市芦淞区2018-2019年上学期期末考试初三英语试题卷卷面分值:150分考试时间:120分钟第一部分听力技能(共两节, 满分30分)略第二部分知识运用(共两节, 满分30分)第一节语法填空从A、B、C三个选项中选择最佳答案填空。
(共10小题,计10分)21.--Mike, do you know which CDs belong to ________ ? I want to take them home.--I have no idea. You may ask Alice.A.sheB.youC.me22.--Do you have any plans for this summer vacation? --I’m not sure. I ______take a trip to Taiwan.A.mustB.shouldC.may23.The art festival of our school _______successfully at the end of last month.A.was heldB.is holdingC.will be hold24.I’ve heard that Zhuhai Chimelong Ocean Kingdom is one of ________ ocean park in Asian.rgeB.much largerC.the largest25.--These bananas are about 5 kilos______ total.Would you like to buy them? --Sure. How much are they?A.forB.inC.on26.I’m not sure when he will be back, but he’s supposed _________ sometime next week.A.returningB.returnC.to return27.The red skirt _________my mother bought for me is made of cotton.A.thatB.whenC.who28.--Jim, how do your parents like country music?-- _______ my dad _______ my mom likes it. They both like country music.A.Either... orB.Neither...norC.Not only...but also29.In my opinion, we can improve our oral English _______ we often practice talking with others.A.butB.ifC.though30.--I don’t understand _______ last night. --I’m sorry. But I was doing my homework.A.why you didn’t watch the music concert on TVB.why didn’t you watch the music concert on TVC.why you don’t watch the music concert on TV第二节词语填空通读下面的短文, 掌握其大意,然后从各题所给的A、B、C三个选项中选出最佳答案。
(共10小题, 计20分)My parents always told me that I couldn't dance, because it was a girl’s sport. But I never gave up my dream of becoming a dancing star. I practiced secretly. However, without my parents' support, that 31.________ seemed impossible to reach.One summer, my little sister Maggie was going to dance lessons. What a 32._______ chance to learn dancing!One afternoon, I was practicing a new dance in my room, when Maggie walked 33.________.“What’s the matter, Maggie?” I stopped 34.________.“Dennis, you are a great dancer! Can you help me?There’ll be a dancing performance in my school, 35.________ all the boys think I'm slow, and none of them wants to be my partner. Could you dance with me for it?” She looked at me hopefully.I agree. In the following months, we 36.________ every evening, hiding from my parents. I was having a fantastic time and soon Maggie improved a lot.Finally came the big day. I became 37.________ when I heard my parents would come to watch the performance. As the 38.________ began, I took a deep breath and tried to calm down. From the cheering of the crowd, I was sure we had 39.________.My 40. _______ put his hand on my shoulder. “Well done, Son. Though it is hard for me to admit(承认) it, it seemed that you really belong to this stage(舞台). Go for it and make us proud.”I'd been waiting for this moment for so long. I knew that the road ahead wasn't going to be easy, but I wouldn't give up. I wanted nothing more in life than to dance.31. A.place B.dream C.answer32. A.boring B.funny C.good33. A.in B.away C.through34. A.drawing B.dancing C.singing35. A.but B.or C.so36. A.chatted B.decided C.practiced37. A.shy B.angry C.nervous38. A.music B.lesson C.movie39. A.arrived B.finished C.succeeded40. A.father B.classmate C.sister第三部分阅读技能(共三节, 满分40分)第一节图表理解阅读下列图表, 从每题所给的A、B、C三个选项中, 选出最佳选项回答问题或完成句子。
(共5小题, 计10分)A41.It is a logo of a famous ______.A.bookstoreB. universityC. post office42.Which of the following is right?A.The color of the logo is dark green.B.There are three books in the main part of the logo.C.The letters “VERITAS” in the logo means “peace” in Latin.B43.______of the books in the form were written by American writers.A.OneB. TwoC. Three44.The book that came out in 1957 was written by ________ .A.Gary D. SchmidtB. Paulo CoelhoC. Theodore Geisel45.Which of the following is NOT true according to the information above?A.Only one of the books won the Newbery Medal.B.The theme of The Cat in the Hat is a natural and easy attitude to life.C.The Alchemist came out in 1988 when the writer was 84 years old.第二节短文理解阅读下列短文, 从每题所给的A、B、C三个选项中, 选出最佳选项回答问题或完成句子。
(共20小题, 计30分)C"When can I get a cell phone?" The answer is when your parents think you need one, though many kidsseem to be getting them around age 12 or 13. Some younger kids may have them because their parents seeit as a matter of safety and convenience. For example, a kid can call mom and dad when sports practice isover. And a cell phone can give kids almost instant access (快捷通道) to their parents if something goeswrong or they need help. It can give parents quick access to their kids so they can check on them andmake sure they're OK.If you do get a cell phone, make some rules with your parents, such as how many minutes you'reallowed to spend on the phone, when you can use your phone, when the phone must be turned off, andwhat you will do if someone calls you too often, and so on.You'll also have to learn to take care of the phone in your life. Keep it charged (充电) and store it in thesafe place so it doesn't get lost. And whatever you do, don't use it in the bathroom. I know someone whodropped her phone in the toilet!46. Parents buy cell phones for their kids because _____.A. they think it is necessaryB. they think their kids are old enoughC.they want to follow their kids wherever they are47. The author of the passage _____.A. wants to describe how children use cell phonesB. knows nothing about when children can have a cell phoneC. may have done a survey on kids using cell phones48. What’s the meaning of the underlined word “charge”?A. 控制B. 充电C. 关闭49. Who is the passage most probably written by?A. Parents who have bought phones for their kids.B. Someone who does cell phone business.C. A teacher who cares most about school safety.50. Which might not be a rule for kids with a cell phone?A. Keep it on all the time.B. Take care not to lose it.C. Don't use it in the bathroom.DNo one knows exactly when jazz was invented, or by whom. But it is said that it began in the early 1900s.Jazz was a new kind of music, for America and the world, and New Orleans was its birthplace.Who were the jazz pioneers? Most were blacks. This music was not written down, and at first only blacks played it. It was hard for white musicians to learn the new style. But soon they were playing jazz, too.The popularity of this music spread. From New Orleans, it traveled up the Mississippi to Chicago, then to Kansas City and New York. By the 1920s, there were many jazz musicians, both black and white. Many of them were famous. One man was better than the rest. His name was Louis Armstrong.Louis Armstrong was a born musician. He was not only talented but also hard-working. He also had a good sense of humor and a big, good-natured smile. These personal qualities were valuable in his rise to fame. After he became famous, he traveled around the world. It seemed that everyone wanted to hear Louis play. But life was not always easy, especially at the beginning.Louis Armstrong was born in 1900 in New Orleans. His father never went to school and his mother could hardly read. When Louis was still a kid, his parents separated, and Louis lived with his mother. How hard their life was can readily be imagined. And yet Louis smiled through everything. He later wrote, “My whole life has been happiness. Life was there for me and I accepted it. Whatever happened has been beautiful to me. I love ev erybody.”51.What can we know exactly from the first paragraph?A.Who invented jazz.B. When jazz was invented.C. Where jazz was invented.52.The underlined word “they” in Paragraph 2 refers to(指)________.A.White musicians.B. Jazz pioneers.C. Black musicians.53.What made Louis Armstrong become the best jazz musician?A.His family background.B. His talent and hard work.C. His good sense of humor.54.Which of the following best expresses Louis Armstrong’s attitude (态度) to life?A.Without music, life is a journey through a desert.B. Failure is the mother of success.C. When you smile, the world smiles back.55.What is the passage mainly about?A.The development of jazzand its best musician.B. The influence of jazz on Americans.C. The achievements of Louis Armstrong.ESaturday, June 16th In the morning, we went camping along a path in Green Natural Park. We were happy because it was a sunny day. We were expecting an enjoyable two-day holiday. On the way, we kept singing and making jokes.However, in the aft ernoon, when we finished our picnic at one o’clock, it was dark and windy. Soon, there was a shower. Unluckily, none of us brought an umbrella. We ran around but we could find no place to hide in.Twenty minutes passed and it was still raining. There were hours to go before we reached the campsite(野营地). It was even worse that our small compass(指南针) showed that we went to the wrong way. We had lost our way!We had to make a quick decision as it was raining heavily. Chris said we could set up a tent to hide in, so Mary and Tom helped to set up the tent. Chris and I tried to make a fire to keep us warm. But we were unable to light thefire, as everything was wet. We dried ourselves, chatted and waited inside the tent. At about five o’clock, it stopped raining. We decided to give up the camping trip because all of us had been very tired.This camping trip may not be very successful but we know each other better. And the most important thing I’ve learned from this trip is the importance of team spirit(精神).56.The passage could be read in a _______.A.diary bookB. grammar bookC.science magazine57.The underlined word “compass” means _________ in Chinese.A.指南针B. 气手枪C. 起重器58.Chris suggested that they should _______ in the rain.A.set up a tentB.reach the campsiteC.find a place to hide in59.Which of the following is NOT true?A.It was sunny in the morning.B.None of them had an umbrella.C.They gave up the camping trip at last.D.They ran a round to dry themselves.60.The writer has learned the importance of _______ from the trip.A.making a decisionB.working togetherC.enjoying holidays第四部分写作技能(共三节, 满分50分)第一节语篇翻译阅读下面的短文, 将划线部分译成英文或中文。