2012中考朝阳一模

北京市朝阳区九年级综合练习（一）物 理 试 卷 2012.5学校 班级 姓名 考号第I 卷（选择题36分）一．下列各题均有四个选项，其中只有一个是符合题意的。

请把该选项前字母填在题前〔 〕内。

（共24分，每小题2分）［ ］1．下列物理量中，以科学家的名字瓦特作为单位的物理量是A．电流B ．电压C ．电阻D ．电功率［ ］2．图1所示的四种现象中，属于光的直线传播现象的是［ ］3．图2所示的各种用具在使用中，属于省力杠杆的是［ ］4．在图3所示的各种自然现象中，属于凝华的是［ ］5．在图4所示的四种情境中，人对物体做功的是考生须知1.本试卷共8页,共五道大题,40道小题，满分100分，考试时间120分钟。

2.在试卷和答题卡上准确填写学校名称，姓名和准考证号。

3.试题答案一律填涂或书写在答题卡上，在试卷上作答无效。

4.考试结束，请将本试卷和答题卡一并上交。

图1D A B C 景物在镜中成像手在墙上形成手影 山在水中形成“倒影” 钢勺好像在水面处折断了 小明用力推货箱, 深秋的早晨大雾弥漫 初冬的早晨霜打枝头春天里冰雪消融 夏天的早晨花草上有露水 图3 A B C D 钓鱼竿 食品夹 核桃夹 托盘天平 BC D 图2 D图7 A 电热取暖器抽油烟机 电视机 家用微波炉 B C D 图9图8［ ］6．下列措施中，能使蒸发变快的是A ．把蔬菜用保鲜膜包好放入冰箱B ．把湿衣服晒在室外通风处C ．把新鲜的柑橘装入塑料袋D ．酒精灯不用时要加盖子［ ］7．如图5所示的四种家用电器中，利用电流热效应工作的是［ ］8．图6所示的跳伞运动员在空中匀速下落的过程中A ．动能一定增大B ．机械能一定不变C ．重力势能一定减小D ．机械能一定增加［ ］9．家庭用电冰箱中消耗电能的器件主要是电动压缩机和照明灯泡，其中电动压缩机M 受温控开关S 1控制，照明灯泡L 受门控开关S 2控制，要求它们既能单独工作又能同时工作，图7是几个同学画的家用电冰箱的电路图，其中正确的是［ ］10．如图8所示电路，电源两端电压保持不变。

2012年北京市朝阳区中考英语一模试卷四、单项填空（共13分，每小题1分）从下面各题所给的A、B、C、D四个选项中，选择可以填入空白处的最佳选项．1. John is in trouble now．Let's go and help _________．（）A himB hisC herD hers2. I was born ________ May 14．What about you？（）A atB inC onD for3. Hurry up，________ you will be late for the meeting．（）A soB orC andD but4. ﹣________ do you usually go to visit your grandmother？﹣By bus．（）A HowB WhenC WhereD Why5. ﹣Who is ________ in your school，Mr．Wang，Mr．Gao or Miss Li？﹣Miss Li，of course．（）A popularB more popularC most popularD the most popular6. There's ________ in the meeting room．Shall we have a talk there？（）A somebodyB anybodyC nobodyD everybody7. ﹣Must I answer the question in English？﹣No，you ________．You can answer it in Chinese．（）A shouldn'tB can'tC mustn'tD needn't8. ﹣Have you seen Mr．Smith？﹣Yes．Look，he ________ the flowers in the garden．（）A watersB is wateringC wateredD has watered9. ﹣My sister is ill in hospital．﹣I'm sorry ________ that．（）A hearB heardC to hearD hearing10. Rose ________ English since 2002．She's got a lot of teaching experience．（）A has taughtB will teachC teachesD taught11. Mr．Green _______ his lessons when I went into his office．（）A preparesB preparedC is preparingD was preparing12. A park ________ here next year．Then people nearby can come for a walk．（）A will buildB will be builtC has builtD was built13. ﹣Lisa，could you tell me ________ last night？﹣Oh，I went to the cinema．（）A where you wentB where did you goC where you will goD where will you go五、完形填空（共12分，每小题12分）阅读下面的短文，掌握其大意，然后从短文后各题所给的A、B、C、D四个选项中，选择最佳选项．14. It was a very cold night, Sunday, February 6．Patrick heard his dog barking （狗叫声） in the garage （车库）．He went there with some food to （1）________ it down．Standing in the middle of the garage was a little girl with her body covered by snow, crying．"Please come and help, "she said．"I think my mom is dead．My brother isin the truck．"After a dinner of pizza at her mother's house in Alton, Carrion, 26, had bundled （捆绑） her（2）________ kids, Averie, four, and Abel, 21months, into a pickup truck and （3）________ home．It was 8p．m．, snow covered the land．（4）________ cars were on the road．Suddenly, the truck began to slide （滑动）．It rolled （转动） two or three times before （5）________ to a stop, tilted into a snow bank on its passenger side．Carrion blacked out．"When I came to, I could hear Abel crying．It was dark, and I couldn't see anything, "Carrion says．Finally, she （6）________ to push the heavy driver's door open enough so that the lights turned on．She saw A bel in his seat．His nose was bloody, but he had no other hurts．Averie was nowhere in sigh t．Carrion called Averie again and again．But there was only （7）________．Then she called 9-1-1．Averie had been awake when the truck stopped rolling．The little girl called her mother, b ut she didn't answer．Averie wriggled （蠕动）（8）________ the broken passenger's window．She walked a quarter of a mile．A house came into view, she stumbled （蹒跚） out of the snow and into the （9）________ garage, and a dog started barking．When she got Patrick's help, she began to （10）________．Patrick jumped into his car and went to search for the （11）________．Up ahead he saw the lights of police cars．"I think I have who you're looking for, "P atrick told the police．One thing Carrion is sure of: her daughter's courage and personality．"Averie is very grow n-up for her （12）________, "she says．"The way she walked all that way to help us…She's so smart, so brave．"（1）A turnB putC quietD slow（2）A sleepyB tiredC shyD weak（3）A leftB passedC gotD headed（4）A ManyB SeveralC SomeD Few（5）A comingB goingC runningD returning（6）A managedB triedC startedD decided（7）A snowB coldC silenceD dark（8）A aroundB throughC fromD across（9）A safeB emptyC warmD open（10）A cheerB cryC relaxD explain（11）A accidentB placeC policeD doctor（12）A abilityB knowledgeC ageD experience六、阅读下列短文，根据短文内容，从短文后各题所给的A、B、C、D四个选项中，选择最佳选项．（共26分，每小题6分）15. What do you think is important in your life? Here are some ideas for you to share．（1）Where does Davy come from？________A The US．B Australia．C Japan．D Germany．．（2）Who tells us to take one thing at a time？________A Davy．B Alice．C Noah．D Austin．．（3）What is Austin's idea？________A Making a plan is important．B Money is important but not all．C Always looking for the good．D Actions speaks louder than words．16. Ever get the feeling that time goes by faster as you get older? I remember when I was nine, the whole year seemed to step by so slowly．School took a long time to end each day and let's not talk about exams．I thought I'd never turn double 10．Now in my thirties, it's like someone's hit the accelerator pedal （加速踏板） and these years are going by much faster．It's 2012and I'm wondering what happened to the last12months!It feels like I sneezed （打喷嚏） in January 2011and that's blown me into January 2012．I'm looking at my 2011To﹣Do List and I've only done one thing﹣read 20new books．I feel sad and regret not spending enough time on the other things．Back to my 20121ist of things that I would like to do the next 12months:①Interview the presid ent②Have a trip to Africa③Board the fastest plane④Write a bookNo.1, 2and 4have been on the list for ten years．I don't know when they'll be done．But it's really fun to make a list at the start of the year．（1）What does the writer feel about the time in these years？________A It goes very slowly．B It goes much faster．C It seems to havestopped． D It seems as fast as before．．（2）The writer feels sad when she looks at her 20111ist because________．A she hasn't finished anythingB she hasn't finished one thingC she has finished everythingD she has just finished one thing．（3）What is the writer's attitude towards No.1，2and 4on her 20121ist？________A She will succeed in doing them．B She isn't going to do any of them．C She will try to do one of themD She isn't sure if they can be done．17. When I moved to the country 20years ago, I took a job as a school bus driver．I'd never had any interest in driving schoolchildren to and from school, but 10years later, I was still working on the school bus．There are so many good reasons why I stayed．Firstly, it was the conversations that brought me different kinds of information．I also got to hear all the family secrets of thenewcomers who were afraid to be starting at a new school．I have a toy bear who was a great comforter for the little ones．The kids got to look after him on the trip to school and he waited patiently for them to get on for the trip home．Our bus would often pass a place where we could see some alpacas （羊驼） in front of a farm house．Little Michael would cry excitedly from the seat, "Look, Miss!Look at the camels!"He used to put his head out of the bus window．When I warned him that a fly would come into his nose if he wasn't careful, he smartly gave up the habit．I remember a little girl got on the bus one morning 5years ago and cried loudly all the way to school．We arrived at the school gate．As she waited to get down the bus stairs, she threw her arms around my neck and sobbed （抽泣） that her grandfather had died the night before．A school bus driver needs to keep one eye on the road and the other on the mirror to watch what the little ones are doing down the back．My catchphrase （口头禅） each day was that I was"taking the monsters （怪兽） to their mothers"．Now, it's necessary to think how many lives I've been responsible for throughout the years, and how many kilometers I've driven in order to get my passengers home safely．I've enjoyed it, but after 20years, it's time to rest and park my school bus for good．Long live the school bus driver!（1）When did the writer begin to be a school bus driver？________A 5years ago．B 10years ago．C 20years ago．D 30years ago．．（2）The writer enjoyed her job because________．A driving was her hobbyB children made her valuableC drivers were paidwell D she liked the environment．（3）What is the writer's future plan？________A She decides to give up the job．B She tries to go on driving．C She wants to havea holiday． D She hopes to have more kids．18. Not long ago, I opened an interesting e﹣mail from Jennifer in Canada．We became friends．One day, she invited me and 11other women to a"Movie Night"to be held every six weeks at her house．We'd talk, eat and watch feel﹣good movies．I e﹣mailed her back immediately: I was in．Research shows that gatherings such as Jennifer's make sense．In a US study, researchers measured （测量） the happiness of 4739people over 20years．The study found that a person's happiness depends on the happiness of people he connects with．Surprisingly, it also found that happiness spreads not only between direct friends, but also among friends of your friends'friends!And those good feelings seem to have the greatest influence among friends of the same sex （性别）．"People with more good friends are less likely to develop depression （情绪低落） and worry, "says Dr．Toupey Luft．"Though you can't choose your family or workmates, you do have control over friendships．"With a little effort, you can add more positive （正面的）relationships to your social circle．Here's how:"Nobody is all positive or all negative, "says Luft．"But there are people you may feel morepositive．Use that as your way to check people and keep records．"When spending time with others, pay attention to your feeling．Are you feeling tired and unhappy? To help you keep records, Luft suggests taking a moment when you get home to write down what your feeling is when around them．While it's great to gather with positive friends, it's also good to stay with others in the same life situations．"But if you're all just complaining （抱怨） and nothing is changing, it's not healthy, "says Luft．Are your friends negative, or are you doing most of the complaining? Considering the answers to these questions can help you decide if you want to stand in front of them．Or you could let the relationship disappear slowly．Sometimes your hobbies can lead to true friendships．Check out newspapers and websites to find a group or class for something you enjoy．These friends can always be there for you and can care each other through difficulties, illness and death．Not into groups? Look for individual （个人的） communication instead．Luft says, "Set small goals, such as having coffee with one new person, and develop friendship according to a plan．If someone suggests going for lunch sometime, set a date．""If you're feeling disappointed （失望） with a friend, try talking about what you both need, "says Luft．For example, tell her what you want during hard times in your lives．________．With some friends you laugh and have fun together at the movies﹣and that can be enough．With others, you pay attention to your deep connection．（1）What does your happiness depend on，according to the passage？________A How many friends you have．B How people you connect with feel．C What situation you are in now．D What kind of friends you have．．（2）What does the first suggestion want us to do？________A To measure our happiness．B To check people around．C To join a group for hobbies．D To leave negative friends．．（3）Which of the following is true？________A All the suggestions tell us to add positive relationship to our social circle．B It's necessary to complain about something but not right to do so for long．C Joining a group can bring better friendship than making individual friends．D We often have many friends during good times but few during hard times．．（4）The underlined sentence in the last paragraph means that________．A when your friend leaves you，you need comfortB when your friend is sad，you should call her upC people may behave differently during hardtimes D friends'needs may be quite different sometimes．七、阅读短文，根据短文内容，从短文后的五个选项中选出能填入空白处的最佳选项．选项中有一项为多余选项．（共8分，每小题8分）19. I'd just got in a taxi at the railway station when suddenly I found one of my suitcases （手提箱） missing．Just then，I saw a young man，not very far，opening it and takingout valuables．"Stop thief!Stop thief!"I shouted and threw open the car door and rushed out to him，followed by the driver and some passers﹣by．（1）_______．My driver caught him by the neck and took out the valuables from his trouser pocket and put them back into my suitcase．Half an hour later，I sat back in the taxi and breathed a sight of relief （松了一口气）．But as I checked those stolen things，I became very surprised，unable to speak．（2）_______．And a blood test report of a 58﹣year﹣old woman appeared．I suddenly realized that the taxi driver must have mistaken the thief's things and put his into my suitcase．（3）_______．But this story keeps coming back to me．Was the young man a habitual thief or a dutiful son who had been driven to find money to save his mother's life？（4）_______．How I wish I had gone back that afternoon to return the money and the report and say sorry to him．For the first time in my life，I realized that hate and love are very close．八、阅读短文，根据短文内容回答问题．（共10分，每小题10分）20. If you drive in New Zealand，it is necessary for you to take a little time to learn the road rules﹣for your own and others'safety．There are a few things that you might find different from driving in your country．Here's some information to help make your driving experience in New Zealand a safe and enjoyable one．Keep leftIn New Zealand，traffic travels on the left﹣hand side of the road and thedriver sits on the right of the car．When you are turning，you should be careful to the left side．Remember to keep your eyes on the road ahead．It is easy to draw your attention to the beautiful parts in New Zealand．Crossing‘Give Way'ruleIf you're turning，give way to all cars that are not turning．In all other situations，give way to cars crossing or coming from your right．One lane（行车道） bridgesMany roads in New Zealand have one lane bridges on them．At one lane bridges，cars travelling in one direction must give way to cars going in the other direction．Any of the signs （标志） shown in the left picture mean that you are coming to a one lane bridge．Slow down and check for traffic coming the other way．The smaller arrow shows which direction has to give way．Animals on the roadWatch out for farm animals on the road，especially in the countryside．When you see them，please slow down．You may need to stop and let the animals go past you or move slowly up behind and follow the farmer's instructions．SeatbeltsIt is a law that all the drivers must wear their seatbelts．If you are caught not wearing your seatbelt，you will be fined．More informationInformation on road safety，including the New Zealand Road Code are available （可得到的）by going to www．nzta．govt．nz or by phoning New Zealand Transport Agency 0800 699 000or visit aa．co．nz．64．Does traffic travel on the left side of the road in New Zealand？________65．What should drivers do when they see the sights in Picture 3while driving？________ 66．When do drivers need to follow the farmer's instructions？________67．How many road rules in New Zealand are mentioned？________68．What does the writer want to tell us？________．九、完成句子（共10分，每小题2分）根据中文意思完成句子．21. 该上课了，我们做好准备吧．________ class．Let's get ready for it．22. 我很高兴，你已经赶上了班里的多数同学．________ that you've already caught up with most of the students in our class．23. 今晚尽可能早睡，因为明天你必须早起．Go to bed________ this evening because you must get up early tomorrow．24. 修理完桌椅后，我们才回家．________ until we finished repairing the desks and chairs．25. 为了保持健康，你不仅应该戒烟，而且应该考虑每天花点儿时间锻炼身体．In order to keep healthy，you should________ taking exercise every day．十、文段表达（15分）根据中文和英文提示，写一封意思连贯、符合逻辑、不少于60词的回信．信的开头和结尾已给出，其词数不计入所完成的回信内．请不要写出你的校名和姓名．26. 假设你叫李利，是英国中学生大卫的笔友．你收到了他的来信，请你给他写一封回信，回答他的问题，并就这些问题谈谈你的认识和对学校生活的感受．2012年北京市朝阳区中考英语一模试卷答案1. A2. C3. B4. A5. D6. C7. D8. B9. C10. A11. D12. B13. A14. CADDAACBDBAC15. ACC16. BDD17. CBA18. BBAD19. D,E,B,A20. Yes,They should slowdownandcheckfortrafficcomingtheotherway,When they see farm animals．,Five/5,Some road rules21. It's time for22. I'm very glad23. as early as possible24. We didn't go home25. not only stop smoking but also think about spending a little time26. Hi!David，I'm glad to get your letter and I'd like to tell you everything．Our school life has two different sides．On one hand，our teachers are really strict with us （老师严格）We stay at school for about 7 or 8 hours a day．（每天待七八个小时）And we usually spend two hours doing our homework after class．（课后两小时做作业）On the other hand，our teachers love us very much，so they want us to be perfect．At school，we study so many subjects and they are both useful and interesting．Our homework helps us review what we've learned in class．【高分句型一】It's really necessary．（我的认识）In a word，our school life is busy but happy．（对学校生活的看法）【高分句型二】I enjoy my school life very much．I hope what I've said can help you．Yours，Li Li。

2012朝阳一模21. It is ____ short distance from here to _____ shopping center, so you can walk there if you like.A. 不填; 不填B. a; 不填C. the; theD. a; the22. I can’t remember how the tune goes, ______ I’ll recognize it when I hear it.A. soB. butC. becauseD. unless23. ––Has anything new been discussed on that problem so far?––_____, and more will follow, I think.A. MuchB. ManyC. LittleD. Few24. Provide your doctor with a detailed medical history ______ he can give you the accuratetreatment.A. even ifB. in caseC. so thatD. as though25. The heavy snow lasted for a week, _____ a serious traffic confusion in the whole area.A. causingB. causedC. having causedD. being caused26. —Has Linda come back from Canada?—Yes. She _____ there for eight years．A. has stayedB. staysC. stayedD. had stayed27. ––I didn’t go to work yesterday because my car broke down.––You _____ mine. I wasn’t using it then.A. might borrowB. should borrowC. must have borrowedD. could have borrowed28. ______ valuable experience, he asked to be sent to remote areas.A. To gainB. GainingC. GainedD. Being gained29. The seats ______ for children and seniors are right at the front of the buses.A. reservedB. reservingC. to reserveD. having reserved30. There are many examples throughout the world ______ talented players are ignored by theirnational managers.A. whenB. whereC. whichD. whose31. ––Have you seen my e-mail about our TESL project?––Yes. Luckily I checked my e-mails yesterday. Normally I ______ my e-mail box for days.A. haven’t openedB. didn’t openC. hadn’t openedD. don’t open32. We must read between the lines, and sometimes _____ the lines, to fully understand the writer.A. withinB. amongC. besidesD. beyond33. He is quite strange, for everything he does is opposite to _____ is considered normal behavior.高三英语试题第1页（共16页）A. whetherB. thatC. whatD. which34. Jane was elected chairman of the committee. This is the first time that a woman ______ to thepost.A. has appointedB. had appointedC. has been appointedD. had been appointed35. ––Do you think it wise for parents to do everything for their children?––No. That’s ______ they’re mistaken.A. whetherB. whenC. whatD. where第二节完形填空（共20小题；每小题1.5分，共30分）阅读下面短文，掌握其大意，从每题所给的A、B、C、D四个选项中，选出最佳选项，并在答题卡上将该项涂黑。

2012-2013学年北京市朝阳区九年级综合练习（一）数 学 试 卷 2013.5一、选择题（本题共32分，每小题4分） 1.-3的倒数是（ ）A ．13 B ．13- C ． 3 D ．-3 2．“厉行勤俭节约，反对铺张浪费”势在必行．最新统计数据显示，中国每年浪费食物总量折合为粮食大约是200000000人一年的口粮．将200000000用科学记数法表示为 A ．8210⨯ B ．9210⨯ C ．90.210⨯ D ．72010⨯3． 若一个正多边形的一个外角是72°，则这个正多边形的边数是（ ）A ．10 B ．9 C ．8 D ．5 4．如图，AB ∥CD ，E 是AB 上一点，EF 平分∠BEC 交CD 于点F ，若∠BEF =70°，则∠C 的度数是（ ）A ．70° B ．55° C ．45° D ．40°5．掷一枚质地均匀的正方体骰子，骰子的六个面上分别刻有1到6的点数大于4的概率为（ ）A ．61 B ．31 C ．41 D ．216．把方程2630x x ++=化成()2x n m +=的形式，正确的结果为A ．()236x += B ．()236x -= C ．()2312x += D ．()2633x +=7．某校春季运动会上，小刚和其他16名同学参加了百米预赛，成绩各不相同，小刚已经知道了自己的成绩，如果只取前8名参加决赛，他想知道自己能否进入决赛，还需要知道所有参加预赛同学成绩的 A . 平均数 B . 众数 C . 中位数 D . 方差8．如图，将一张三角形纸片ABC 折叠，使点A 落在BC 边上，折痕EF ∥BC ，得到△EFG ；再继续将纸片沿△BEG 的对称轴EM 折叠，依照上述做法，再将△CFG 折叠，最终得到矩形EMNF ，折叠后的△EMG 和△FNG 的面积分别为1和2，则△ABC 的面积为A . 6B . 9C . 12D . 18 二、填空题（本题共16分，每小题4分）9．在函数12y x =+中，自变量x 的取值范围是 ．10．分解因式：3m m -= .11．如图，AB 为⊙O 的弦，半径OC ⊥AB 于点D ，AB =32，∠B =30°，则△AOC 的周长为 .12. 在平面直角坐标系xOy 中，动点P 从原点O 出发，每次向上平移1个单位长度或向右平移2个单位长度，在上一次平移的基础上进行下一次平移．例如第1次平移后可能到达的点是（0，1）、（2，0），第2次平移后可能到达的点是（0，2）、（2，1）、（4，0），第3次平移后可能到达的点是（0，3）、（2，2）、（4，1）、（6，0），依此类推……．我们记第1次平移后可能到达的所有点的横、纵坐标之和为l 1，l 1=3；第2次平移后可能到达的所有点的横、纵坐标之和为l 2，l 2=9；第3次平移后可能到达的所有点的横、纵坐标之和为l 3，l 3=18；按照这样的规律，l 4= ； l n = (用含n 的式子表示，n 是正整数)． 三、解答题（本题共30分，每小题5分） 13．计算：()0223tan 602013--︒+．14．求不等式13(1)x x +>-的非负整数解.15．已知2270x x --=，求2(2)(3)(3)x x x -++-的值． 16．已知：如图，OP 平分∠MON ，点A 、B 分别在OP 、ON 上，且OA =OB ，点C 、D 分别在OM 、OP 上，且∠CAP =∠DBN ．求证：AC =BD ．17.如图，在平面直角坐标系xOy 中，一次函数y = -x 的图象 与反比例函数()0ky x x=<的图象相交于点()4A m -，． （1）求反比例函数ky x=的解析式； （2）若点P 在x 轴上，AP =5，直接写出点P 的坐标．18.北京地铁6号线正式运营后，家住地铁6号线附近的小李将上班方式由自驾车改为了乘坐地铁，这样他从家到达上班地点的时间缩短了0.3小时．已知他从家到达上班地点，自驾车时要走的路程为17.5千米，而改乘地铁后只需走15千米，并且他自驾车平均每小时走的路程是乘坐地铁平均每小时所走路程的23．小李自驾车从家到达上班地点所用的时间是多少小时？ 四、解答题（本题共20分，每小题5分）19. 如图，在四边形ABCD 中，∠D =90°，∠B =60°，AD =6，AB =3， AB ⊥AC ,在CD 上选取一点E ，连接AE ，将△ADE 沿AE 翻折，使点 D 落在AC 上的点F 处． 求（1）CD 的长； （2）DE 的长．20. 如图，⊙O 是△ABC 是的外接圆，BC 为⊙O 直径，作∠CAD =∠B ，且点D 在BC 的延长线上．(1)求证：直线AD 是⊙O 的切线；(2)若sin ∠CAD=4，⊙O 的半径为8，求CD 长．21. “2012年度中国十大科普事件”今年4月份揭晓，“PM2.5被写入‘国标’，大气环境质量广受瞩目”名列榜首．由此可见，公众对于大气环境质量越来越关注，某市对该市市民进行一项调查，以了解PM2.5浓度升高时对人们户外活动是否有影响，并制作了统计图表的一部分如下：（1）结合上述统计图表可得：p = ，m = ； （2）根据以上信息，请直接补全条形统计图；（3）若该市约400万人，根据上述信息，请你估计一下持有“影响很大，尽可能不去户外活动”这种态度的约有多少万人．（说明：“PM2.5”是指大气中危害健康的直径小于2.5微米的颗粒物，也称可入肺颗粒物）22．阅读下面材料：小雨遇到这样一个问题：如图1，直线l 1∥l 2∥l 3 ，l 1与l 2之间的距离是1，l 2与l 3之间的距离是2，B PM 2.5浓度升高时对于户外活动 公众的态度的扇形统计图2%试画出一个等腰直角三角形ABC ，使三个顶点分别在直线l 1、l 2、l 3上，并求出所画等腰直角三角形ABC 的面积．小雨是这样思考的：要想解决这个问题，首先应想办法利用平行线之间的距离，根据所求图形的性质尝试用旋转的方法构造全等三角形解决问题．具体作法如图2所示：在直线l 1任取一点A ，作AD ⊥l 2于点D ，作∠DAH =90°，在AH 上截取AE =AD ，过点E 作EB ⊥AE 交l 3于点B ，连接AB ，作∠BAC =90°，交直线l 2于点C ，连接BC ，即可得到等腰直角三角形ABC ．请你回答：图2中等腰直角三角形ABC 的面积等于 ． 参考小雨同学的方法，解决下列问题：如图3，直线l 1∥l 2∥l 3, l 1与l 2之间的距离是2，l 2与l 3之间的距离是1,试画出一个等边三角形ABC ，使三个顶点分别在直线l 1、l 2、l 3上，并直接写出所画等边三角形ABC 的面积（保留画图痕迹）．五、解答题（本题共22分，第23题7分，第24题7分，第25题8分） 23．二次函数2134y x x n =++-的图象与x 轴只有一个交点；另一个二次函数2222(1)46y nx m x m m =--+-+的图象与x 轴交于两点，这两个交点的横坐标都是整数，且m 是小于5的整数．求（1）n 的值；（2）二次函数2222(1)46y nx m x m m =--+-+的图象与x 轴交点的坐标．24．在Rt △ABC 中，∠A =90°，D 、E 分别为AB 、AC 上的点．（1）如图1，CE =AB ，BD =AE ，过点C 作CF ∥EB ，且CF =EB ，连接DF 交EB 于点G ，连接BF ，请你直接写出EBDC 的值； （2）如图2，CE =kAB ，BD =kAE ，12EB DC =，求k 的值．l 1l 2l 3图325．如图，二次函数y =ax 2+2ax +4的图象与x 轴交于点A 、B ，与y 轴交于点C ，∠CBO 的正切值是2．(1)求此二次函数的解析式．(2)动直线l 从与直线AC 重合的位置出发，绕点A 顺时针旋转，与直线AB 重合时终止运动，直线l 与BC 交于点D ，P 是线段AD 的中点． ①直接写出点P 所经过的路线长．②点D 与B 、C 不重合时，过点D 作DE ⊥AC 于点E 、作DF ⊥AB 于点F ，连接PE 、PF ，在旋转过程中，∠EPF 的大小是否发生变化？若不变，求∠EPF 的度数；若变化，请说明理由． ③在②的条件下，连接EF ，求EF 的最小值．北京市朝阳区九年级综合练习（一）数学试卷参考答案及评分标准 2013.5一、选择题（本题共32分，每小题4分）1.B 2.A 3.D 4.D 5.B 6.A 7.C 8.C 二、填空题（本题共16分，每小题4分）9．x ≠-2 10.(1)(1)m m m +- 11.6 12.30；()312n n +（说明：结果正确，不化简整理不扣分）.（每空2分） 三、解答题（本题共30分，每小题5分）13原式114=-…4分34=-.……5分 14.解：133x x +>- …1分 24x ->-2x <.…3分∴原等式的非负整数解为1，0.…5分15. 解：原式22449x x x =-++- …2分2245x x =--.……3分∵2270x x --=，∴227x x -=.……4分∴原式22(2)5x x =--9=.…5分16.证明：∵OP 平分∠MON ，∴∠COA =∠DOB .……1分∵∠CAP =∠DBN ，∴CAO DBO ∠=∠.……2分∵OA =OB ，………3分∴COA ∆≌DOB ∆. ……4分∴AC =BD . ……5分17.（1）解:把()4A m -，代入y = -x ，得m =4.…1分 ∴()44A -，. ………2分把()44A -，代入k y x =，得k = -16.∴反比例函数解析式为16y x=-. ……3分 （2）（-7，0）或（-1，0）.…5分18. 解：设小李自驾车从家到达上班地点所用的时间是x 小时…1分由题意，得 17.51520.33x x =⨯-.…2分解方程，得 x =0.7.…3分经检验，x =0.7是原方程的解，且符合题意.……4分答：小李自驾车从家到达上班地点所用的时间是0.7小时.……5分 四、解答题（本题共20分，题每小题5分）19．解：（1）∵AB ⊥AC ，∴∠BAC =90°.∵∠B =60°，AB，∴AC =10.…1分∵∠D =90°,AD =6， ∴CD =8. ………2分（2）由题意，得∠AFE =∠D=90°，AF=AD =6， EF=DE .∴∠EFC =90°, ∴FC =4.…3分设DE =x ,则EF=x ,CE=8-x . 在Rt △EFC 中，由勾股定理,得 2224(8)x x +=-.……4分解得x =3.所以DE =3.…5分20.（1）证明：连接OA .∵BC 为⊙O 的直径，∴∠BAC =90°.………1分∴∠B +∠ACB∵OA=OC ，∴∠OAC =∠OCA .∵∠CAD =∠B ，∴∠CAD +∠OAC =90°.即∠OAD =90°.∴OA ⊥AD .∴AD 是⊙O 的切线.………2分(2) 解：过点C 作CE ⊥AD 于点E .∵∠CAD =∠B ,∴sinB =sin ∠CAD =4.……3∵⊙O 的半径为8，∴BC=16. ∴AC =sin BC B ⋅= ∴在Rt △ACE 中，CE=sin AC CAD ⋅∠=2.…4分 ∵CE ⊥AD , ∴∠CED =∠OAD =90°. ∴CE ∥OA . ∴△CED ∽△OAD .∴CD CE OD OA =.设CD =x ，则OD =x +8.即8x x =+5分21.解：（1）30%，20%； ………………………2分 （2）如图；………………………………4分（3）400×20%=80（万人）. …………5分22. 解： 5；………2分 如图； ……3分 …5分五、解答题（本题共22分，第23题7分，第24题7分，第25题8分） 23. 解：(1)∵2134y x x n =++-的图象与x 轴只有一个交点，∴令10y =，即2304x x n ++-=.………1分123B∴131404n ⎛⎫∆=--= ⎪⎝⎭.解得n =1.……2分 (2)由(1)知，()2222146y x m x m m =--+-+.∵()2222146y x m x m m =--+-+的图象与x轴有两个交点，∴[]2222(1)4(46)m m m ∆=----+820m =-.∵20∆>，∴52m >.……3分 又∵5m <且m 是整数，∴m =4或3.…5分当m =4时，2266y x x =-+的图象与x 轴的交点的横坐标不是整数；当m =3时，2243y x x =-+，令20y =，即2430x x -+=，解得11x =，23x =.综上所述，交点坐标为（1，0），（3，0）.…7分24. 解：(1)EB DC =……2分 (2)过点C 作CF ∥EB 且CF =EB ，连接DF 交EB 于点G , 连接BF .∴四边形EBFC 是平行四边形.…3分∴CE ∥BF 且CE =BF .∴∠ABF =∠A =90°.∵BF =CE =kAB .∴BF k AB =.∵BD =kAE ，∴BDk AE=.……4分 ∴BF BD AB AE =.∴DBF ∆∽EAB ∆……5分∴DFk BE=,∠GDB=∠AEB .∴∠DGB =∠A =90°. ∴∠GFC =∠BGF =90°.∵12CF EB DCDC==.∴DF DF EB CF==∴k……7分25. 解：(1)根据题意，C (0，4)．∴OC =4．∵tan ∠CBO =2，∴OB =2．∴B (2，0)．…………1分∴ 0444a a =++．∴12a =-． ∴二次函数的解析式为2142y x x =--+．………2分 (2) ①点P……………………………………………3分 ②∠EPF 的大小不发生改变．………………………………………………………4分 由2142y x x =--+可得，A (-4，0)． ∴OA = OC ．∴△AOC 是等腰直角三角形． ∴∠CAO =45°．∵DE ⊥AC ， DF ⊥AB ， ∴∠AED = ∠AFD =90°． ∵点P 是线段AD 的中点，B∴PE= PF =12AD= AP．∴∠EPD=2∠EAD，∠FPD=2∠F AD．∴∠EPF =∠EPD+∠FPD =2∠EAD +2∠F AD= 2∠CAO=90°．…………………5分③由②知，△EPF是等腰直角三角形．∴EF．……………………………………………………………6分∴当AD⊥BC时，AD最小，此时EF最小．……………………………………7分在Rt△ABD中，∵tan∠CBO=2，AB=6，∴AD=5．∴EF =5．即此时EF．……………………………………………………8分说明：各解答题其它正确解法请参照给分．。

2012北京市语文中考各区一模试题汇编名著阅读【东城】8.名著阅读（3分）儒家经典《孟子》相传所作。

它长于言辞，善于用例。

《生于忧患，死于安乐》一文开头一连列举了六个历史人物在逆境中成长的例子，是为了阐明的观点；《鱼我所欲也》则用的事例，论证了即使普通人也有“舍生取义”之心的看法。

答案：孟子及其门人生于忧患（乞人）不受嗟来之食（共3分。

共3空，每空1分）【西城】8．名著阅读（3分）《诗经》是我国最早的一部诗歌总集，收录了从西周到①时期的诗歌305篇，故也称“②”，这些诗歌分为“风”“雅”“颂”三个部分，其中《蒹葭》属于“风”“雅”“颂”中的“③”。

答案：春秋诗三百风（国风）评分标准：共3分。

共3空，每空1分，该空有错不得分。

【朝阳】8．名著阅读（3分）强调人的道德修养是儒家思想的重要组成部分，“己所不欲勿施于人”，孔子告诫我们要胸怀宽广，宽恕待人；①认为人都有“本心”，道义尊严比生命更为重要，《②》一文中的“舍生取义”和③的故事讲的都是这个道理。

答案：①孟子②鱼我所欲也③不受嗟来之食（行道之人和乞丐不接受施舍）（共3分。

每空1分，有错该空不得分）【海淀】8．名著阅读（3分）我国第一部诗歌总集《诗经》，收入自西周初年至春秋中叶五百多年的诗歌305篇。

先秦称为“诗”，或“诗三百”。

西汉时被①尊为经典，始称“诗经”。

《诗经》中的许多诗歌采用了起兴的表现方法，如《关雎》中“关关雎鸠，在河之洲”，就是以雎鸠起兴，引出淑女和君子；又如《蒹葭》中“②”，就是用③起兴，引出④。

答案：①儒家②蒹葭苍苍，白露为霜③蒹葭④伊人（共3分。

共4空，①②空，每空1分；③④空每空0.5分）【通州】8．名著阅读（3分）《论语》是①家学派的经典著作之一，由孔子的弟子及其再传弟子编撰而成。

记录了②的言行，集中体现了孔子的政治主张、道德观念、教育原则及学习方法等，如“礼让为国”、“见贤思齐”、“有教无类”。

关于学习方法的语录“学而不思则罔，思而不学则殆”，阐述了③的辩证关系。

北京市朝阳区九年级综合练习（一）数学试卷参考答案及评分标准2012.5一、选择题（本题共32分，每小题4分） 题号 1 2 3 4 5 6 7 8 答案 ADBDDACC二、填空题 （本题共16分，每小题4分，）9. x ≥4 10. ))((5b a b a m -+ 11. 70° 12. 32，1+n n（每空2分） 三、解答题（本题共30分，每小题5分） 13. 解：原式1223633-+⨯-= ……………………………………………………4分1=. …………………………………………………………………………5分 14. 解：x x 5322<+-. …………………………………………………………………2分13-<-x . …………………………………………………………………3分∴31>x . ……………………………………………………………………4分 这个不等式的解集在数轴上表示为：……………………5分15. 证明：∵C 是AE 的中点，∴AC ＝CE . …………………………………………………………………………1分 ∵BC∥D E ，∴∠ACB=∠E . ……………………………………………………………………2分 在△ABC 和△CDE 中，⎪⎩⎪⎨⎧=∠=∠∠=∠CE AC E ACB D B ， ∴△ABC ≌△CDE . ………………………………………………………………4分 ∴ AB ＝CD . ………………………………………………………………………5分16. 解： )1(3)1()2(422---++x x x x331284222+-+-++=x x x x x4622++=x x ………………………………………………………………………3分4)3(22++=x x .∵0132=-+x x ，∴132=+x x . (4)分∴原式＝6. ……………………………………………………………………………5分17. 解：（1）∵PN 垂直x 轴于点N ，PM 垂直y 轴于点M ，矩形OMPN 的面积为2 ，且ON =1，∴PN ＝2.∴点P 的坐标为（1,2）. ………………………1分 ∵反比例函数ky x=（x ＞0）的图象、一次函数 y x b =+的图象都经过点P ，由12k=，b +=12得2=k ，1=b . ∴反比例函数为xy 2=，………………………………………………………2分一次函数为1+=x y . ………………………………………………………3分（2）Q 1（0,1），Q 2（0,－1）. ……………………………………………………5分18. 解：∵四边形ABCD 是平行四边形，∴421===AC CO AO ，BO DO =. ∵△EAC 是等边三角形，∴8==AC EA ，EO ⊥AC . ………………………………………………………2分 在Rt△ABO 中，322=-=AO AB BO .∴DO ＝BO ＝3. ………………………………………………………………………3分在Rt△EAO 中，3422=-=AO EA EO . …………………………………4分∴334-=-=DO EO ED . (5)分四、解答题（本题共21分，第19、20、21题每小题5分，第22题6分） 19. 解：设缩短发车间隔前平均每分钟运送乘客x 人. ……………………………………1分根据题意，得xx 128005014400=+， …………………………………………………………………3分解得400=x . ………………………………………………………………………4分 经检验，400=x 是原方程的解. …………………………………………………5分答：缩短发车间隔前平均每分钟运送乘客400人.20. （1）证明：∵D A=DB ，∴∠DAB=∠DBA . 又∵∠C =∠DBC ，∴∠DBA ﹢∠DBC ＝︒=︒⨯9018021. ∴AB ⊥BC .又∵AB 是O ⊙的直径，∴BC 是O ⊙的切线. ………………………………………………………2分（2）解：如图，连接BE ，∵AB 是O ⊙的直径，∴∠AEB ＝90°. ∴∠EBC ＋∠C ＝90°. ∵∠ABC ＝90°，∴∠ABE ＋∠EBC ＝90°. ∴∠C ＝∠ABE .又∵∠AFE ＝∠ABE ， ∴∠AFE ＝∠C .∴sin ∠AFE ＝sin ∠ABE ＝sin C . ∴sin ∠AFE ＝53. …………………………………………………………………3分连接BF ，∴︒=∠90AFB . 在Rt△ABE 中，25sin =∠=ABEAEAB . ……………………………………4分∵AF ＝BF ，∴5==BF AF . (5)分21. 解：（1）① 0.15%)4.31(5.14≈+⨯， ………………………………………………2分即2010年北京市人均绿地面积约为15.0平方米.②……………………………………3分（2）675300406544936251100=⨯⨯+⨯+⨯+⨯+⨯+⨯. …………………5分 估计她所在学校的300名同学在2011年共植树675棵.22. 解：（1）x y 6.01=. ………………………………………………………………………1分x x y 2.22.022+-= (3)15.315.014.513.612.618人均公共绿地面积（m 2）1512963020072008200920102011年份FEO DBCA（2）)2.22.0()10(6.02t t t W +-+-=，66.12.02++-=t t W (4)分即2.9)4(2.02+--=t W .所以甲种蔬菜进货量为6吨，乙种蔬菜进货量为4吨时，获得的销售利润之和最大，最大利润是9200元. …………………………………………………6分五、解答题（本题共21分，第23题6分，第24题8分，第25题7分）23. 解：（1）22=BD . ……………………………………………………………………2分（2）把△ADC 沿AC 翻折，得△AEC ，连接DE ，∴△ADC ≌△AEC .∴∠DAC =∠EAC ，∠DCA =∠ECA ， DC ＝EC . ∵∠BAD =∠BCA =2∠DAC =30°， ∴∠BAD =∠DAE =30°，∠DCE =60°.∴△CDE 为等边三角形. ……………………3分 ∴DC ＝DE .在AE 上截取AF ＝AB ，连接DF ， ∴△ABD ≌△AFD . ∴BD ＝DF .在△ABD 中，∠ADB =∠DAC ＋∠DCA =45°， ∴∠ADE =∠AED =75°，∠ABD =105°. ∴∠AFD =105°. ∴∠DFE =75°. ∴∠DFE =∠DEF . ∴DF ＝DE .∴BD ＝DC ＝2. …………………………………………………………………4分 作BG ⊥AD 于点G ， ∴在Rt△BDG 中， 2=BG . ……………………………………………5分∴在Rt△ABG 中，22=AB . ……………………………………………6分FGEDABC24. 解：（1）∵32++=bx ax y 过点M 、N （2，－5），6=MN ，由题意，得M （4-，5-）. ∴⎩⎨⎧-=+--=++.53416,5324b a b a解得 ⎩⎨⎧-=-=.2,1b a∴此抛物线的解析式为322+--=x x y . …………………………………2分 （2）设抛物线的对称轴1-=x 交MN 于点G ，若△DMN 为直角三角形，则32121===MN GD GD . ∴D 1（1-，2-），2D （1-，8-）. (4)分直线MD 1为1-=x y ，直线2MD 为9--=x y . 将P （x ，322+--x x ）分别代入直线MD 1，2MD 的解析式，得1322-=+--x x x ①，9322--=+--x x x ②. 解①得 11=x ，42-=x （舍），∴1P （1,0）. …………………………………5分 解②得 33=x ，44-=x （舍），∴2P （3,－12）. ……………………………6分 （3）设存在点Q （x ，322+--x x ），使得∠QMN =∠CNM .① 若点Q 在MN 上方，过点Q 作QH ⊥MN ，交MN 于点H ，则4tan =∠=CNM MHQH. 即）（445322+=++--x x x .解得21-=x ，42-=x （舍）.∴1Q （2-，3）. ……………………………7分 ② 若点Q 在MN 下方，同理可得2Q （6，45-）. …………………8分xy P 2D 2D 1G MNCO P 1x y HQMNC O25. 解：（1）在矩形ABCD 中，90A D ∠=∠=︒，AP =1，CD =AB =2，∴PB= 5，90ABP APB ∠+∠=︒． ∵90BPC ∠=︒，∴90APB DPC ∠+∠=︒． ∴ABP DPC ∠=∠． ∴ △ABP ∽△DPC ．∴AP PBCD PC=，即152PC =． ∴PC=25．……………………………………………………………………2分 （2）① ∠PEF 的大小不变．理由：过点F 作FG ⊥AD 于点G ． ∴四边形ABFG 是矩形． ∴90A AGF ∠=∠=︒．∴GF=AB=2，90AEP APE ∠+∠=︒．∵90EPF ∠=︒，∴90APE GPF ∠+∠=︒．∴AEP GPF ∠=∠．∴ △APE ∽△GFP . …………………………………………………………4分 ∴221PF GF PE AP ===． ∴在Rt△EPF 中，tan∠PEF=2PFPE=．……………………………………5分即tan∠PEF 的值不变．∴∠PEF 的大小不变．…………………………………………………………6分② 5. (7)分G F P D C A B E P DC(F)A B(E)。

1.生 3. 须 知 1. 2. 3. 4. 5. 6. 7. 8. 2012年北京市朝阳区初三一模试卷数学本试卷共5页，共五道大题，25道小题，满分120分.考试时间120分钟.在试卷和答题纸上认真填写学校名称、班级和姓名.试题答案一律填涂或书写在答题纸上，在试卷上作答无效. 在答题纸上，作图题用 2B 铅笔作答，其他试题用黑色字迹签字笔作答. 考试结束，请将本试卷、答题纸和草稿纸一并交回. 、选择题（本题共32分，每小题4分）下面各题均有四个选项，其中只有一个计算：2 ,9 =（） A. 1 B . 3 我市深入实施环境污染整治， 某经济开发区的 吨.将167000用科学记数法表示为（） A. 167 103 B . 16.7 104 已知，如图, A. 40 因式分解 A. x C. 3 D. 5 40家化工企业中已关停、整改 C. 1.67 105 D. 0.167 是符合题意的. 32家，每年排放的污水减少了 167000106AD 与BC 相交于点 B . 50° O, AB// CD 如果/ B = 20°,/ D = 40°,那么/C. BOD 为()60°D. 70° 9的结果是（B . xC . D. x 10 如图，是由一些相同的小正方体搭成的几何体的三视图, A. 2个 B . 3个 C . 搭成这个几何体的小正方体的个数有 4个 D. 6个 已知抛一枚均匀硬币正面朝上的概率为A. B. C. D. 1 ，下列说法正确的是（） 2次正面朝上 连续抛一枚均匀硬币 2次必有连续抛一枚均匀硬币 10次都可能正面朝上 大量反复抛一枚均匀硬币，平均每 100次出现下面朝上50次 通过抛一枚均匀硬币确定谁先发球的比赛规则是公平的 如图，AB 是O O 的直径，AB= 4, AC 是弦，AC= 2 3 , / AOC 为() A. 120° B. 130° C. 140° 如图，在△ ABC 中,/ ACB= 90°, AC= BC= 2. E 、 EH L AB 于点H,设AE= x , GH h y ,下面能够反映 D F 分别是射线AC CB 上的动点，且 y 与x 之间函数关系的图象是（） 150°AE= BF EF 与AB 交于点G每小题4分）二、填空题（本题共16分,护―3自变量的取值范围是 _____________ .k点P 在双曲线y — (k 0)上，点P (1,2)与点P 关于y 轴对称，则此双曲线的解析式为x11 .如图，线分别与边 AB, AC 交于点M N 若OM MN 则点M 的坐标为12.如图，点 A , A, A, A,…，A 在射线 OA 上，点 B , R, B ，…，B —1 在射线 OB 上，且 AB // A 2B 2// AB ?// …// A n —1B n —1,AB // AE 2// AiB? / …// A>E n —1, △ A A 2B1 ,△ A 2A 3B 2,…，△ A —1AB —1 为阴影三角形，若△ ABB ,A ABB 3 的面积分别 为1、4,则厶AAB 的面积为 ________________ ;面积小于201115. 已知：如图， A 点坐标为 3, 0 , B 点坐标为0, 3 .2(1) 求过A , B 两点的直线解析式； (2) 过B 点作直线BP 与x 轴交于点P ，且使OP 2OA ，求 ABP 的面积.(2)解方程组x 2y 3x 2y9.函数y10.如图, 在平面直角坐标系中，等边三角形ABC 的顶点B, C 的坐标分别为(1，0)，(3，0)，过坐标原点 O 的一条直的阴影三角形共有、解答题(本题共30分，每小题5分)(⑹.13.计算：2 112 4si n60个.16. 如图，分别以Rt △ ABC勺直角边AC及斜边AB向外作等边△ ACD等边△ ABE已知/ BA& 30o, EFl AB,垂足为F,连结DF.（1）求证：AC= EF;（2）求证：四边形ADFE1平行四边形.17 .先化简: x2x 3 —3i（i 3）；若结果等于2，求出相应x的值. 4x 9 2 2x 3 318.在某市举办的“读好书，讲礼仪”活动中，东华学校积极行动，各班图书角的新书、好书不断增多，除学校购买外，还有师生捐献的图书.下面是七年级（1）班全体同学捐献图书的情况统计图：请你根据以上统计图中的信息，解答下列问题：（1）该班有学生多少人？（2）补全条形统计图；（3）七（1）班全体同学所捐献图书的中位数和众数分别是多少？四、解答题（本题共20分，每小题19 .某批发商以每件50元的价格件T恤.第一个月以单价80 售出了200件；第二个月如果变，预计仍可售出200件，批加销售量，决定降价销售，根查，单价每降低1元，可多售件，但最低单位应高于购进的5分）购进800元销售，单价不发商为增据市场调出10价格；第A4 ' 血窗书（制）二个月结束后，批发商将对剩余的T恤一次性清仓销售，清仓时单价为40元.设第二个月单价降低x元(1)填表(不需要化简)时间第一个月第二个月清仓时单价(元)80▲40销售量(件)200▲▲(2)如果批发商希望通过销售这批T恤获利9000元，那么第二个月的单价应是多少元?20.如图，等腰梯形ABCDh AD/ BC AD= AB= CD= 2，/ C= 60°, M是BC的中点.(1)求证：△ MD(是等边三角形；(2)将厶MD(绕点M旋转，当MD即MD )与AB交于一点E, M(C即MC )同时与AD交于一点F时，点E, F和点A构成厶AEF试探究△ AEF的周长是否存在最小值•如果不存在，请说明理由；如果存在，请计算出△AEF周长的最小值.21. 如图，已知△ ABC，以BC为直径，O为圆心的半圆交AC于点F，点E为弧CF的中点，连接BE交AC于点M，AD ABC的角平分线，且AD BE，垂足为点H .(1)求证：AB是半圆O的切线；(2)若AB 3，BC 4，求BE 的长.22.已知：如图1,矩形ABCDK AB= 6，BC= 8，E、F、G H分别是AB BC CD DA四条边上的点(且不与各边顶点重合)，设m^ A聊BO CDF DA探索m的取值范围.(1)__________________________________________________________________ 如图2，当E、F、G H分别是AB BC CD DA四边中点时，m= ____________________________________________________________(2)为了解决这个问题，小贝同学采用轴对称的方法，如图3,将整个图形以CD为对称轴翻折，接着再连续翻折两次，从而找到解决问题的途径，求得m的取值范围.①请在图1中补全小贝同学翻折后的图形；②m的取值范围是______________ .五、解答题(本题共22分，第23题7分，第24题7分，第25题8分) 23. 已知一元二次方程 x + ax + a — 2= 0.(1) 求证：不论a 为何实数，此方程总有两个不相等的实数根；(2) 设a v 0,当二次函数y = x 2+ ax + a — 2的图象与x 轴的两个交点的距离为时，求出此二次函数的解析式； (3)在(2)的条件下，若此二次函数图象与 x 轴交于A B 两点，在函数图象上是否存在点P,使得△ PAB 的面积为 色丄3,2 若存在求出P 点坐标，若不存在请说明理由.24. 如图，在△ ABC 中，点 D 是 BC 上一点，/ B =Z DA = 45° (1) 如图1,当/ C = 45。

朝阳区2012年九年级综合练习语文试卷2012．5 一、选择。

下面各题均有四个选项，其中只有一个符合题意。

（共12分。

每小题2分）1．下列词语中加点字的读音有误的一项是A．蓓蕾(lěi)哺育(bǔ)联袂(mèi) 不屈不挠(náo)B．坎坷(kē)伫立(zhù) 氛围(fēn)斤斤计较(jiào)C．活泼(pō)瞥见(piē)粗犷(ɡuǎnɡ) 毛遂自荐(suì)D．倔强(jué) 恣意(zì) 狭隘(ài) 水涨船高(zhǎnɡ)2．依据对下列各组词语中加点字的解释，判断词语意思都不正确的一项是A．期．盼不期．而遇解释：“期”有“盼望”的意思。

判断：“期盼”指期待，盼望；“不期而遇”指不盼望某人却正好遇见。

B．断言．不言．而喻解释：“言”有“说”的意思。

判断：“断言”指十分肯定地说；“不言而喻”指不用说就可以明白。

C．琐屑．不屑．置辩解释：“屑”有“琐碎”的意思。

判断：“琐屑”指琐碎；“不屑臵辩”指事情太琐碎，不值得争辩。

D．顾．客三顾．茅庐解释：“顾”有“看”的意思。

判断：“顾客”指来商店看东西的人；“三顾茅庐”指多次到茅庐中看别人。

3．下列句子中加点的词语运用不正确的一项是A. 科学的巨大成就很多都是以大胆的幻想为出发点的。

科技工作者，需要有思想，敢于异想天开，才有可能成为杰出的科学家。

B. 在学校的诗歌鉴赏研讨会上，一位著名诗人进行了精彩的演讲，既有班门弄斧的谦逊，又有旁征博引的渊博，受到了同学们的热烈欢迎。

C. 书到用时方恨少，有些人在参加工作以后才发现自己所学是那么不足，感叹自己在上学时没有能注意积蓄足够的学识与能力。

D. 中美两国在一些问题上出现纷争，这是正常的。

我们“不能一叶障目，不见泰山”，应该看到对话与合作仍是两国关系的主流。

4．结合语境，将下列句子填入横线处，最恰当的一项是我喜欢秋天的雨。

淅淅沥沥的秋雨，①。