14.数列{an}中...且.则常数t= ▲ . 查看更多

 

题目列表(包括答案和解析)

任务型阅读(共10小题,每小题1分,满分10分)

请认真阅读下列短文,并根据所读内容在文章后表格中的空格里填入一个最恰当的单词。注意:每个空格只填一个单词。请将答案写在答题卡上相应的横线上。

Teamwork is just as important in science as it is on the playing field or in the gym. Scientific investigations (调查) are almost always carried out by teams of people working together. Ideas are shared, experiences are designed, data are analyzed, and results are evaluated and shared with other investigators. Group work is necessary, and is usually more productive than working alone.

Several times throughout the year you may be asked to work with one or more of your classmates. Whatever teh task your group is assigned, a few rules need to be followed to ensure a productive and successful experience.

What comes first is to keep an open mind, becasue everyone’s ideas deserve consideration and each group member can make his or her own contribution. Secondly, it makes a job easier to divide the group task among all group members. Choose a role on the team that is best suited to your particular strengths. Thirdly, always work together, take turns, and encourage each other by listening, clarifying, and trusting one another. Mutual support and trust often make a great difference.

Activities like investigations are most effective when done by small groups. Here are some more suggestions for effective team performance during these activities: Make sure each group member understands and agrees to the task given to him or her, and everyone knows exactly when, why and what to do; take turns doing various tasks during similar and repeated activities; be aware of where other group members are and what they are doing so as to ensure safety; be responsible for your own learning, though it is by no means unwise to compare your observations with those of other group members.

When there is research to be done, divide the topic into several areas, and this can explore the issue in a very detailed way. You are encouraged to keep records of the sources used each person, which helps you trace back to the origin of the problems that may happen unexpectedly. A format for exchanging information (e.g. photocopies of notes, oral discussion, etc.) is also important, for a well-chosen method not only strengthens what you present but also makes yourself easily understood. When the time comes to make a decision and take a position on an issue, allow for the contributions of each member of the group. Most important of all, it is always wise to make decisions by compromise and agreement.

After you’ve completed a task with your team, make an evaluation of the team’s effectiveness — the strengths and weaknesses, opportunities and challenges.

Title

Working Together

Theme

Effective performance needs highly cooperated (71) ________

General rules

l  Keep an open mind to everyone’s (72) ________.

l  Divide the group task among group members.

l  (73) ________ and trust each other.

(74) ________

l  Understand and agree to the (75) ________ task of one’s own.

l  Take turns doing various tasks.

l  Show concern for others to ensure safety.

l  Take (76) _________ for one’s own learning.

l  Compare your own observations with those of others.

Explore

an issue

l  Break the (77) ________ into several areas.

l  Keep records of the sources just in (78) ________.

l  (79) ________ your information with others via proper format.

l  Make all decisions by compromise and agreement.

(80) ________

effectiveness

l  Analyze the strengths and weaknesses.

l  Find out the opportunities and challenges.

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完形填空(共20小题;每小题1.5分,满分30分)阅读下面短文,掌握其大意,然后从1—20题各题所给的四个选项(A、B、C和D)中,选出可以填入空白处的最佳选项。

Throughout history man has had to accept the fact that all living things must die. But people now live longer than they   1  . Yet, all living things still show the   2   of aging, which will eventually   3  death.

Aging is not a disease, but as a person passes maturity (成熟期), the cells of the body and the  4 they form do not function as well as they  5  in childhood and teenage years. The body provides less  6   against disease and is more  7  to have accident.

A number of related causes may   8   aging. Some cells of the body have a fairly long life, but they are not   9 when they die. As a person ages,   10  of brain cells and muscle cells decreases.   11  body cells die and are replaced by new cells. In an aging person the   12  cells may not be as workable or as capable  13   growth as those of a young person.

Another  14   in aging may be changes within the cells  15  . Some of the protein chemicals in cells are known   16  with age and become less elastic (有弹性的). This is why the skin of old people wrinkles (皱纹) and   17 . This is also the reason why old people   18  in height. There may be other more important chemical changes in the cells. Some complex cell chemicals, such as DNA and RNA, store and   19  information that the cells need. Aging may affect this  20 and change the information-carrying molecules so that they do not transmit the information as well.

1. A.would                    B.be used to            C.used to               D. used

2. A.function              B.effect                                          C.affect             D. sign

3.    A.lead in             B.give in                 C.run into              D. result in

4.    A.hands             B.feet                    C.heart                 D. organs

5.    A.do                B.has done            C.did                   D. had done

6.    A.energy            B.protection          C.vigor              D. power

7.    A.likely              B.probable            C.possible              D. alike

8.    A.attend to           B.contribute to       C.add to               D. devote to

9.    A.replaced           B.reborn               C.recovered         D. surrendered

10. A.a number          B.the amount        C.the number        D. a great deal

11. A.The others        B.The other         C.Another            D. Other

12. A.old                B.left                 C.new               D. other

13. A.to                  B.for                 C.of                 D. in

14. A.factor              B.effect               C.reason              D. element

15. A.for themselves    B.of themselves   C.themselves       D. on their own

16.   A.change              B.to have changed  C.to change         D. to be changed

17. A.hangs loose       B.hangs loosely       C.is hanging loosely D. is hanging loose

18. A.increase            B.shrink               C.lengthen            D. decrease

19. A.pass away         B.pass by             C.pass off            D. pass on

20. A.improvement      B.procession         C.approach          D. process

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 根据对话内容,从对话后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Policeman:Now, Jimmy, did you get a good view(看清) of the accident?

Jimmy:Oh, yes. I was standing outside the bank building and I saw it quite clearly.

Policeman:Do you know what time it was?

Jimmy:Yes.___1___ It was 2:45 exactly.  

Policeman:Good. ____2____

Jimmy:Well, quite slowly — about 10 miles an hour. It was coming up York Road. ____3____ But they were still red when he went over them.

Policeman:I see. ____4____ was it also driving slowly?

Jimmy:It was coming along Union Street about 30 miles per hour. It was a blue Toyota. ____5____

Policeman:Did you see what colour his traffic(交通) light was?

Jimmy:Yes, it changed to yellow just before he crossed it.

A. What about the car?

B. I checked my watch.

C. Didn‘t you see the car?

D. Now,how fast was the truck moving?

E. Was the car going beyond the speed limit?

F. I suppose the truck driver knew the lights were going to change.

G. The driver stopped his car when he saw the truck crossing the street.

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完形填空(共20小题,每小题1.5分,满分30分)

阅读下面短文,掌握其大意,然后从36—55题各题所给的四个选项(A、B、C和D)中,选出可以填入空白处的最佳选项。

In 1989 an 8.2 earthquake almost flattened America, killing over 30,000 people in less than four minutes. In the middle of complete damage and disorder, a father rushed to the school where his son was supposed to be, ___36__ that the building was __37__.

After the unforgettably shock, he __38__ the promise he had made to his son: "No matter __39__, I'll always be there for you!" And tears began to __40__ his eyes. As he looked at the pile of ruins, it looked hopeless, but he kept remembering his __41__ to his son. He rushed there and started ___42__ the ruins.

As he was digging, other helpless parents arrived, ___43__: "It's too late! They're all dead! ___44__, face reality, there's nothing you can do!" To each parent he responded with __45__: "Are you going to help me now?" No one helped. And then he continued to dig for his son, stone by stone.

Courageously he went on alone because he needed to know __46__: "Is my boy __47__ or is he dead?" He dug for eight hours...12 hours...24 hours...36 hours...then, in __48__ hour, he pulled back a large stone and heard his son's __49__. He screamed his son's name, "ARMAND!" He heard back, "Dad!?! It's me, Dad! I told the other kids not to worry. I told them that if you were alive, you __50_ me and __51_ you saved me, they'd be saved. You promised, 'No matter what happens, I'll always be there for you!' You did it, Dad!"

"What's going on in there? " the father asked.

"There are 14 of us __52__ __53__ 33,dad. We're scared, hungry, thirsty and thankful you're here. When the building collapsed, it made __54__, and it saved us."

"Come out, boy!"

"No, Dad! Let the other kids out first, __55__ I know you'll get me! No matter what happens, I know you'll always be there for me!"

36. A.only discovering         B.only to discover     

C.only realizing         D.only to realize

37. A.as flat as a pancake       B.as high as a mountain

C.as strong as an ox    D.as weak as a kitten

38. A.memorized  B.forgot      C.kept D.remembered

39. A.what      B.what happen    C.which      D.who

40. A.fill        B.fill in       C.come       D.burst

41. A.picture   B.promise   C.present     D.encourage

42. A.digging B.digging through      C.digging out     D.digging into

43. A.to say     B.said C.and saying       D.saying

44. A.Come out      B.Come again     C.Come on D.Come off

45. A.one word      B.one sound       C.one row   D.one line

46. A.for himself    B.of himself       C.by himself       D.to himself

47. A.live       B.living      C.alive        D.lively

48. A.38 B.the 38      C.38th D.the 38th

49. A.sound    B.voice       C.noise       D.tone

50. A.will save       B.would save       C.save D.would have saved

51. A.when     B.because    C.even if     D.though

52. A.remained       B.missing    C.left   D.gone

53. A.for        B.behind     C.out of      D.over

54. A.a promise      B.space       C.room       D.a triangle

55.A.because    B.though     C.when       D.even though

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完形填空(共20小题;每小题1.5分,满分30分)

阅读下面短文,掌握其大意,然后从16~35各题所给的A、B、C、D四个选项中,选出最佳选项。

Roberta appeared on the stage.She took a deep breath and began to   16   .Now she was Portia,a strong-willed   17    in Shakespeare’s The Merchant of Venice.The theater was filled with people.She was speaking with a power she had never before experienced,the words flowing

   18    from her.

  19  .Roberta had never acted in her life before the audition(选拔试演).She  20    being in front of other people.She was very   21    at school.She had never thought she was good enough at anything to  22   much attention.She stayed mostly to herself,making  23   friends.She had excellent grades,   24    she always thought that something was missing.

Two weeks before the audition,Roberta’s mother had heard about it and   25    her to join in.

“I can’t think of anyone else better suited to   26    the part.Remember all the plays you used to act out for us?”

Roberta looked down.“I’m not interested.”

Her mother wouldn’t let the   27    drop.“You’re just a little scared(害怕).Everyone gets scared.You know you   28   do it.The trick is to look past the   29    to find the love of what you’re doing.”

So Roberta had made an appointment(预约)with the head of the Drama Club.She had read the play and found herself excited by the  30  of speaking such rich words.In secret she practiced Portia’s part,  31   the lines by repeating them over and over.It wasn’t hard;she  32    every minute of it.Every time she spoke the words,she had a new  33    of the lines,as if Shakespeare had written Portia on many levels.

On the day of the audition,she   34    two of Portia’s famous speeches for the auditors.When she had finished,the head of the Drama Club announced the   35    was hers.

16.A.sing                            B.dance                      C.speak                        D.report

17.A.member                B.actress                       C.player                       D.character

18.A.weakly                 B.rapidly                      C.smoothly                   D.slowly

19.A.At first                 B.In fact                       C.After all                    D.In all

20.A.hated                    B.enjoyed                     C.appreciated                D.regretted

21.A.honest                  B.shy                           C.polite                        D.patient

22.A.avoid                   B.focus                        C.pay                           D.attract

23.A.few                      B.a few                        C.several                      D.many

24.A.or                        B.so                             C.for                            D.but

25.A.forced                  B.requested                   C.encouraged                D.reminded

26.A.accept                  B.play                          C.offer                         D.learn

27.A.role                      B.matter                       C.interest                      D.grade

28.A.can                      B.must                         C.may                          D.should

29.A.anger                   B.pain                          C.sadness                      D.fear

30.A.purpose                B.way                          C.idea                          D.importance

31.A.memorizing                                             B.organizing

C.checking                                                      D.improving

32.A.disliked                B.loved                        C.expected                    D.bore

33.A.consideration                                           B.description

C.selection                                                       D.understanding

34.A.practiced                     B.planned                     C.performed                 D.delivered

35.A.part                      B.play                          C.speech                       D.position

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1.C   2.A   3.B   4.D   5.C   6.B   7.D   8.C   9.B  10.A

  11.120°   12.3x+y-1=0   13.   14.10    15.100    16.(1),(4)

17.解:(1)设抛物线,将(2,2)代入,得p=1. …………4分

∴y2=2x为所求的抛物线的方程.………………………………………………………5分

(2)联立 消去y,得到. ………………………………7分

设AB的中点为,则

∴ 点到准线l的距离.…………………………………9分

,…………………………11分

,故以AB为直径的圆与准线l相切.…………………… 12分

(注:本题第(2)也可用抛物线的定义法证明)

18.解:(1)在△ACF中,,即.………………………………5分

.又,∴.…………………… 7分

(2)

. ……………………………14分

(注:用坐标法证明,同样给分)

19.

解法一:(1)连OM,作OH⊥SM于H.

∵SM为斜高,∴M为BC的中点,∴BC⊥OM.

∵BC⊥SM,∴BC⊥平面SMO.

又OH⊥SM,∴OH⊥平面SBC.……… 2分

由题意,得

设SM=x,

,解之,即.………………… 5分

(2)设面EBC∩SD=F,取AD中点N,连SN,设SN∩EF=Q.

∵AD∥BC,∴AD∥面BEFC.而面SAD∩面BEFC=EF,∴AD∥EF.

又AD⊥SN,AD⊥NM,AD⊥面SMN.

从而EF⊥面SMN,∴EF⊥QS,且EF⊥QM.

∴∠SQM为所求二面角的平面角,记为α.……… 7分

由平几知识,得

,∴

,即所求二面角为. ……………… 10分

(3)存在一点P,使得OP⊥平面EBC.取SD的中点F,连FC,可得梯形EFCB,

取AD的中点G,连SG,GM,得等腰三角形SGM,O为GM的中点,

设SG∩EF=H,则H是EF的中点.

连HM,则HM为平面EFCB与平面SGM的交线.

又∵BC⊥SO,BC⊥GM,∴平面EFCB⊥平面SGM. …………… 12分

在平面SGM中,过O作OQ⊥HM,由两平面垂直的性质,可知OQ⊥平面EFCB.

而OQ平面SOM,在平面SOM中,延长OQ必与SM相交于一点,

故存在一点P,使得OP⊥平面EBC. ……………………… 14分

 

∵底面边长为1,∴

.    ……………… 1分

平面SBC的一个法向量

∴y=2h,n=(0,2h,1).… 3分

=(0,1,0),由题意,得.解得

∴斜高. …………………………………………………… 5分

(2)n=(0,2h,1)=

由对称性,面SAD的一个法向量为n1. ………………………………6分

设平面EBC的一个法向量n2=(x,y,1),由

,得

 解得.………………… 8分

设所求的锐二面角为α,则

,∴.…………… 10分

(3)存在满足题意的点.证明如下:

. ………………………… 11分

,令与n2共线,则. ……………… 13分

.故存在P∈SM,使OP⊥面EBC.……………………… 14分

20. 解:(1)当n为奇数时,an≥a,于是,. ………………3分

         当n为偶数时,a-1≥1,且an≥a2,于是

=. …………6分

(2)∵,∴公比.……9分

. …………………………………………10分

(注:如用求和公式,漏掉q=1的讨论,扣1分)

 . ……………12分

.……15分21.解:(1)∵,∴,∴. 1分

,即,∴. …3分

①当,即时,上式不成立.………………………………………………4分

②当,即时,.由条件,得到

,解得. ……………………………………………5分

,解得.…………………………………………6分

 m的取值范围是. ………………………………………7分

(2)有一个实根.………………………………………………………………………………9分

,即

,则

. ………………………10分

 △>0,故有相异两实根

,∴ 显然

,∴,∴. …………12分

于是

                    

为三次函数的极小值点,故与x轴只有一个交点.

∴  方程只有一个实根.…………………………15分


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