(2)等比數(shù)列{an}中..前n項(xiàng)的和為An.且A7.A9.A8成等差數(shù)列.設(shè).數(shù)列{bn}前n項(xiàng)的和為Bn.證明:Bn<. 查看更多

 

題目列表(包括答案和解析)

閱讀下面的短文,請根據(jù)短文后的要求答題(請注意問題后的字?jǐn)?shù)要求)

[1]One thing Britain is famous for is pubs, and no trip to the UK would be complete without a visit to one of the thousands of pubs across the country.

[2] Pubs play an important part in the social structure of the country. They are places where all ages and social classes mix to talk, do business, or just spend a couple of quiet hours before heading home in the evening.

[3] There are many different types of beer available in pubs. Traditional British beer is called bitter, or ale, and is usually served at room temperature. As a result, the British are famous for their ‘warm beer’ ! If you prefer a cold beer, ask for lager. This beer is a light yellow in color whereas bitter is usually a darker brown. All beers are served as pints (500ml) or haves (250ml). To order, you need to ask for a pint or half, and then name the beer. So, you could say “          ”.

[4]Wine, red or white, is normally available in all pubs, as are spirits such as whisky, gin or vodka.

[5]It is not, however, necessary to drink alcohol. Non-alcoholic drinks are called soft drinks. You can have juice, lemonade or cola, among others.

[6]If you visit a pub in a group, it is important to pay for your ‘round’. This means that you buy a drink for everyone in your group.  Not buying your round is a big social mistake! Remember that you need to order and pay for your drinks at the bar.

[7]So, follow these tips if you want to get the most out of visiting a pub, and, “cheers!”

1.What is the best title of the passage? (Please answer within 10 words.)

2.Which sentence in the passage can be replaced by the following one?

If you don’t buy a drink for everyone in your group, you are socially wrong.

3.Please fill in the blank in the third paragraph with proper words or phrases to complete the sentence. (Please answer within 1 words.)

4.If you are in a pub, what would you like to drink? Why? (Please answer within 20 words.)

5.Translate the underlined sentence in the second paragraph into Chinese.

 

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First it was jogging. Then aerobics(有氧運(yùn)動). Not too long ago, Americans discovered race walking.
Now Americans are into a new fitness craze. They’re taking up bicycling. Over hills and down mountainsides and across quiet country roads, Americans are busily rolling along.
The number of adults who ride for fitness is around 17 million, an increase of 70 percent over four years ago. Twice as many women as men are coming to the sport. Americans are falling in love with biking because it has speed, the benefits of jogging and beautiful scenery.
Bicycling is a very appropriate sport, which is important to people who injured their knees while jogging or whose joints are aching from aerobics. And biking is a real awakening for people who have been into race walking in the past. Race walking is as dull as watching paint dry.
The most popular kind of bicycle for people who are new to the sport is the mountain bike, which has a fixed frame with wide tires and upright handles. Mountain bikes also have many gears(齒輪) to make it easier to climb hills. About 5 million Americans ride mountain bikes, compared with 200,000 who rode them only five years ago.
Costs range from about $130 for a bottom-of-the-line bicycle to more than $2,700 for an expensive bicycle.
Mountain biking has attracted some people who race down the sides of mountains like a bat out of hell. But most riders ride slowly and they rarely venture far from home.
The biking craze has brought an unexpected profit(盈利) to clothing and bicycle accessory(附屬品)makers. Last year, bikers paid $630 million for biking clothes and accessories.
Bicycling seems likely to continue its fantastic growth.
53. Race walking is about as dull as watching paint dry because _______         
A. race walking is a slow-moving sport
B. the number of adults who ride for fitness has grown 70 percent in four years.
C. it has speed, the benefits of jogging and beautiful scenery.
D. Americans are taking up bicycling.
54. The bicycling craze has been a profit for _______.
A. people who want to ride like a bat out of hell
B. bicycle accessory makers
C. race walkers
D. twice as many women as men
55. What does the underlined word “bottom-of-the-line” mean?
A. poor       B. modern    C. old        D. cheapest
56. The main idea of the article is _______
A. riding a bicycle is one of the most dangerous sports in America
B. Americans are rolling along
C. bicycling is the latest fitness craze to hit America
D. most people in America want to own a hand-made bicycle that can cost more than 2,700

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The Chinese New Year is a great holiday to choose to celebrate Chinese culture with your child. Here are few fun ways to bring a bit of fun and   1   into your home through the festivities of the Chinese New Year.

1.Add a lucky red door. Red is a traditional color of   2  . It's an important part of the Chinese New Year to   3  on doing what one can to bring about good luck for the New Year. If you don't want to  4   the door red, how about wrapping it up like a present with red wrapping paper. If changing your front door's color is not workable, how about the door to your child's bedroom?

2.Eat. A huge part of most cultures is that of food and the Chinese New Year is not   5  , it's eating jiaozi at midnight on New Year's Eve, or longevity noodles on day seven of the festivities to    6  long life. The Chinese New Year celebrations mean many fancy meals that your child will   7  .

3.Create a lantern. Sara Naumann, the Guide to China Travel, shares a bit about the legend of the Lantern Festival or Yuanxiao, which occurs on the   8  day of the Chinese New Year festivities. It's a   9  that includes an emperor, a young woman who misses her family, and tricking the God of Fire. Your kids should love this story. After   10  it with them, or while reading the story, enjoy making your own paper lantern to display.

4.Give lucky money. The Guide to Mandarin Language shares that another very popular   11  during the Chinese New Year is that of the gift of red envelopes with   12  in them. These gifts are given to children and usually follow a bit of superstition(迷信) in that the money needs to be given in even amounts and never contain   13  numbers, such as four. Therefore, four dollars is not a good gift. The envelopes are also decorated with lucky symbols and New Year   14  .

5.Give a small gift. The giving of simple gifts is also an appropriate way to   15  the Chinese New Year. What better gift than that of a children's book about the Chinese New Year or the Chinese Culture.

6.Make some noise. Just like in America, the Chinese use   16  in ringing in their New Year. In the Chinese culture it began as a way to   17   away any demons(鬼) that threaten to bring a profitable and lucky New Year, but today it's also about excitement and   18  . Consider setting off a few firecrackers of your own, if allowed in your area. If not, make a cute firework picture with a bit of glitter and glue. A pretend firecracker is another great craft that could also be considered a festive way to decorate your New Year table.

7.Sing Happy Birthday to your dog. The second day of the Chinese New Year is   19  the birthday of all dogs. Why not   20  your child to throw Fido a birthday celebration? Perhaps an extra ride in the car or new chew toy is in order? I know my dog would appreciate a few extra belly rubs too.

(    ) 1. A. tradition           B. culture             C. civilization       D. habit

(    ) 2. A. wealth              B. disaster             C. belief                      D. luck

(    ) 3. A. focus                      B. accuse              C. adapt               D. mind

(    ) 4. A. boil                 B. paint               C. wash               D. purchase

(    ) 5. A. same               B. similar             C. common           D. different

(    ) 6. A. come about       B. take about        C. bring about       D. get out

(    ) 7. A. bore                 B. destroy             C. enjoy                      D. absorb

(    ) 8. A. last                  B. first                 C. second              D. next

(    ) 9. A. play                 B. story               C. novel                      D. history

(    ) 10. A. sharing           B. listening           C. reading             D. making

(    ) 11. A. invention               B. story               C. race                 D. tradition

(    ) 12. A. food                      B. clothes             C. money              D. jewels

(    ) 13. A. unclear           B. unlucky            C. unfair                   D. uncertain

(    ) 14. A. wishes            B. signs               C. presents            D. happiness

(    ) 15. A. spend             B. envy               C. buy                  D. celebrate

(    ) 16. A. firecrackers     B. songs                      C. dances              D. goods

(    ) 17. A. take                      B. scare               C. get                   D. burn

(    ) 18. A. fun               B. relax               C. sleep               D. travel

(    ) 19. A. fixed                  B. named              C. considered               D. marked

(    ) 20. A. order              B. accompany       C. tease               D. Allow

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根據(jù)提示完成句子。(共15小題,每空1分,滿分15分)

1.___________________(據(jù)估計(jì))the vase is about 2,000 years old.

2._____________(除了……以外) an album, I gave him a dictionary and some novels.

3.______________(在……不在的時候) the manager, it is me who take charge of the company.

4.He dived into the rive to save the drowning girl ______________(毫不猶豫地).

5.After her father’ s retirement, she was _______________ (擁有) of the property of the family.

6.We should be _________________ (與……相處融洽) all our classmates.

7.Your suggestion __________________. (值得考慮)

8.He is very clever, but he doesn’t work hard; ____________ her sister. (他姐姐也是這樣).

9.It is said that yoga _______________ (對……有極大的好處) to human health.

10.When making a plan, you should ____________________(將他的健康納入到考慮之中).

11. It was _________________(這種失敗感) that made him determined to succeed in his new life.

12.Mike ___________________ (比……有優(yōu)勢) you since he can speak English fluently.

13.The giant panda is an ________________(瀕危物種).

14.We _______________ five lovely grandchildren. (我們有幸有五個可愛的孫子孫女)

15.When his father came in, he ___________________(假裝在圖書).

 

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                            B

  What is language for? Some people seem to think it's for practicing grammar rules and learning lists of words—the longer the lists,the better. That's wrong. Language is for the exchange(交流)of ideas and information. It's meaningless knowing all about a language if you can't use it freely. Many students I have met know hundreds of grammar rules, but they can't speak correctly or fluently. They are afraid of making mistakes. One shouldn't be afraid of making mistakes when speaking a foreign language. Native speakers make mistakes and break rules, too. Bernard saw once wrote, "Foreigners often speak English too correctly." But the mistakes that native speakers make are different from those that Chinese students make. They're English mistakes in the English language. And if enough native speakers break a rule, it is no longer a rule. What used to be wrong becomes right. People not only make history, they make language. But a people can only make its own language. It can't make another people's language. So Chinese students of English should pay attention to grammar, but they shouldn't overdo(做過頭)it. They should put communication first. 

1.Language is used to ________.

A. express oneself           B. practice grammar rules

B. talk with foreigners only    D. learn lists of words

2.Generally, when an American or an Englishman speaks English, he ________.

A. never makes mistakes           B. often makes mistakes

C. can't avoid making mistakes      D. always makes mistakes

3."Foreigners often speak English too correctly. "This sentence means that ________.

A. foreigners speak correct English

B. foreigners speak incorrect English

C. foreigners speak English according to the grammar rules

D. foreigners never make mistakes when they speak English

4.If too many native speakers break a rule, ________.

A. what they use will become right  B. they are against the law

C. they should say sorry to others  D. they will become heroes

5.When we speak a foreign language, we should ________.

A. speak in Chinese way       B. speak by the rules

C. speak to native speakers   D. not be afraid of making mistakes

 

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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)設(shè)拋物線,將(2,2)代入,得p=1. …………4分

∴y2=2x為所求的拋物線的方程.………………………………………………………5分

(2)聯(lián)立 消去y,得到. ………………………………7分

設(shè)AB的中點(diǎn)為,則

∴ 點(diǎn)到準(zhǔn)線l的距離.…………………………………9分

,…………………………11分

,故以AB為直徑的圓與準(zhǔn)線l相切.…………………… 12分

(注:本題第(2)也可用拋物線的定義法證明)

18.解:(1)在△ACF中,,即.………………………………5分

.又,∴.…………………… 7分

(2)

. ……………………………14分

(注:用坐標(biāo)法證明,同樣給分)

19.

解法一:(1)連OM,作OH⊥SM于H.

∵SM為斜高,∴M為BC的中點(diǎn),∴BC⊥OM.

∵BC⊥SM,∴BC⊥平面SMO.

又OH⊥SM,∴OH⊥平面SBC.……… 2分

由題意,得

設(shè)SM=x,

,解之,即.………………… 5分

(2)設(shè)面EBC∩SD=F,取AD中點(diǎn)N,連SN,設(shè)SN∩EF=Q.

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

又AD⊥SN,AD⊥NM,AD⊥面SMN.

從而EF⊥面SMN,∴EF⊥QS,且EF⊥QM.

∴∠SQM為所求二面角的平面角,記為α.……… 7分

由平幾知識,得

,∴

,即所求二面角為. ……………… 10分

(3)存在一點(diǎn)P,使得OP⊥平面EBC.取SD的中點(diǎn)F,連FC,可得梯形EFCB,

取AD的中點(diǎn)G,連SG,GM,得等腰三角形SGM,O為GM的中點(diǎn),

設(shè)SG∩EF=H,則H是EF的中點(diǎn).

連HM,則HM為平面EFCB與平面SGM的交線.

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

在平面SGM中,過O作OQ⊥HM,由兩平面垂直的性質(zhì),可知OQ⊥平面EFCB.

而OQ平面SOM,在平面SOM中,延長OQ必與SM相交于一點(diǎn),

故存在一點(diǎn)P,使得OP⊥平面EBC. ……………………… 14分

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    ∵底面邊長為1,∴,

    ,

    .    ……………… 1分

    設(shè),

    平面SBC的一個法向量,

    ,

    ,

    ∴y=2h,n=(0,2h,1).… 3分

    =(0,1,0),由題意,得.解得

    ∴斜高. …………………………………………………… 5分

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

    由對稱性,面SAD的一個法向量為n1. ………………………………6分

    設(shè)平面EBC的一個法向量n2=(x,y,1),由

    ,,得

     解得.………………… 8分

    設(shè)所求的銳二面角為α,則

    ,∴.…………… 10分

    (3)存在滿足題意的點(diǎn).證明如下:

    . ………………………… 11分

    ,令與n2共線,則. ……………… 13分

    .故存在P∈SM,使OP⊥面EBC.……………………… 14分

    20. 解:(1)當(dāng)n為奇數(shù)時,an≥a,于是,. ………………3分

             當(dāng)n為偶數(shù)時,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的討論,扣1分)

     . ……………12分

    .……15分21.解:(1)∵,,∴,∴. 1分

    ,即,∴. …3分

    ①當(dāng),即時,上式不成立.………………………………………………4分

    ②當(dāng),即時,.由條件,得到

    ,解得. ……………………………………………5分

    ,解得.…………………………………………6分

     m的取值范圍是. ………………………………………7分

    (2)有一個實(shí)根.………………………………………………………………………………9分

    ,即

    ,則

    ,. ………………………10分

     △>0,故有相異兩實(shí)根

    ,∴ 顯然,,

    ,∴,∴. …………12分

    于是

                        

    為三次函數(shù)的極小值點(diǎn),故與x軸只有一個交點(diǎn).

    ∴  方程只有一個實(shí)根.…………………………15分


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