如圖.正四面體中.是底面上的高.為的中點.則與所成角的余弦值為 . 查看更多

 

題目列表(包括答案和解析)

現(xiàn)在,學(xué)生的零花錢越來越多,但是亂花錢現(xiàn)象很嚴重。下面是你應(yīng)某晚報教育在線欄目之約針對學(xué)生的零用錢(pocket money)的消費方向,對你市某中學(xué)的高中和初中的部分學(xué)生進行問卷調(diào)查所得出數(shù)據(jù)。請你用英文寫一篇調(diào)查報告,反映調(diào)查結(jié)果,并呼吁中學(xué)生應(yīng)樹立正確的消費觀。

注意:1、書信中不必一一列舉具體數(shù)字,只要抓住主要問題和數(shù)據(jù)說明的問題即可;

   2、開頭已給出,不計入總詞數(shù);

3、詞數(shù)120左右。

Dear Editor,

Recently a survey has been carried out to find out how middle school students spend their pocket money.

 

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現(xiàn)在,學(xué)生的零花錢越來越多,但是亂花錢現(xiàn)象很嚴重。下面是你應(yīng)某晚報教育在線欄目之約針對學(xué)生的零用錢(pocket money)的消費方向,對你市某中學(xué)的高中和初中的部分學(xué)生進行問卷調(diào)查所得出數(shù)據(jù)。請你用英文寫一篇調(diào)查報告,反映調(diào)查結(jié)果,并呼吁中學(xué)生應(yīng)樹立正確的消費觀。

注意:1、書信中不必一一列舉具體數(shù)字,只要抓住主要問題和數(shù)據(jù)說明的問題即可;
   2、開頭已給出,不計入總詞數(shù);
3、詞數(shù)120左右。
Dear Editor,
Recently a survey has been carried out to find out how middle school students spend their pocket money.

查看答案和解析>>

請閱讀下列應(yīng)用文及相關(guān)信息,并按照要求匹配信息。請在答題卡上將對應(yīng)題號的相應(yīng)選項字母涂黑。(如選E請涂AB,如選F請涂CD)

下面是美國著名游記作家Bill Bryson的幾本作品,首先請閱讀它們的封面信息:

A.

A Walk in the Woods: Rediscovering America on the Appalachian Trail

B.

The Lost Continent: Travels in Small-Town America

C.

I’m a Stranger Here Myself: Notes on Returning to America after 20 Years Away

D.

The Road Less Traveled: 1000 Amazing Places off the Tourist Trail

E.

Neither Here nor There: Travels in Europe

F.

The English Landscape: Its Character and Diversity

下面是對這幾本書的簡要介紹,請把它們對應(yīng)的封面信息找出來:

36. In this collection, Bill Bryson is writing from home. We find he assesses life both in New England and in the contemporary United States. With the telescopic perspective(遠望視角) of one who has stepped out of the American mainstream and come back after 20 years, Bryson holds the mirror up to U.S. culture and feel strange to his motherland.

37. This book is a guide to the world’s unspoilt sights and experiences. It presents one thousand fresh and fascinating alternatives to hundreds of well-known tourist destinations and sights, including alternatives to the Carnival in Rio and the beaches of Thailand, the most-visited national parks, over-rated restaurants and holiday sites.

38. Returning to the U.S. after 20 years in England, Bill Bryson decided to reconnect with his mother country by hiking the length of the 2100-mile Appalachian Trail. Awed by merely the camping section of his local sporting goods store, he still goes into the wilderness and learns hard lessons about self-reliance.

39. A travelogue by Bill Bryson is as close to a sure thing as funny books get. This book is no exception. Following an urge to rediscover his youth, the author leaves his native Des Moines, Iowa, in a journey that takes him to across 38 states in the country, which is like a small town in his opinion.

40. Born in Iowa, Bryson backpacked through Europe as a young man. While living in England some 20 years later, he revisited many of the same places from arctic Norway’s northern lights to romantic Capri in Italy. Here he jumps back and forth between old memories and new experiences.

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書面表達。
  日前,針對學(xué)生的零用錢(pocket money)的消費方向,你對你們市某中學(xué)的高中和初中的部分學(xué)生進行了問卷調(diào)查.得出數(shù)據(jù)如下表.現(xiàn)請你用英文給某報社編輯寫一封信,反映這一情況,并呼吁中學(xué)生樹立正確的消費觀.

注意:1.書信中不必一一列舉具體數(shù)字,只要抓住主要問題和數(shù)據(jù)說明問題即可.
         2.字數(shù):120字左右.開頭已給出.不計人總詞數(shù).
Dear editor.
  Recently a survey has been done to find out how middle school students spend their pocket money.
                                                                                                                                                         
                                                                                                                                                    
                                           
                                                                               

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某校高三年級對如何填報高考志愿作了一次問卷調(diào)查,結(jié)果如下圖所示,請根據(jù)圖中信息簡要介紹這次調(diào)查結(jié)果并發(fā)表你個人看法。

約35%的同學(xué)認為

約45%的同學(xué)認為

你的看法

1.應(yīng)以個人興趣為主

2.興趣是成功之母

3.被迫學(xué)自己不感興趣的專業(yè)是痛苦的。

1.應(yīng)以社會需要為主。

2.將來容易找到工作。

3.興趣是可以培養(yǎng)的。

……

    注意:詞數(shù):100詞左右。

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1.解析:,故選A。

2.解析:∵

故選B。

3.解析:由,得,此時,所以,,故選C。

4.解析:顯然,若共線,則共線;若共線,則,即,得,∴共線,∴共線是共線的充要條件,故選C。

5.解析:設(shè)公差為,由題意得,;,解得,故選C。

6.解析:∵雙曲線的右焦點到一條漸近線的距離等于焦距的,∴,又∵,∴,∴,∴雙曲線的離心率是。故選B.

7.解析:∵為正實數(shù),∴,∴;由均值不等式得恒成立,,故②不恒成立,又因為函數(shù)是增函數(shù),∴,故恒成立的不等式是①③④。故選C.

8.解析:∵,∴在區(qū)間上恒成立,即在區(qū)間上恒成立,∴,故選D。

9.解析:∵

,此函數(shù)的最小值為,故選C。

10.解析:如圖,∵正三角形的邊長為,∴,∴,又∵,∴,故選D。

11.解析:∵在區(qū)間上是增函數(shù)且,∴其反函數(shù)在區(qū)間上是增函數(shù),∴,故選A

12.解析:如圖,①當時,圓面被分成2塊,涂色方法有20種;②當時,圓面被分成3塊,涂色方法有60種;

③當時,圓面被分成4塊,涂色方法有120種,所以m的取值范圍是,故選A。

13.解析:做出表示的平面區(qū)域如圖,當直線經(jīng)過點時,取得最大值5。

學(xué)科網(wǎng)(Zxxk.Com)14.解析:∵,∴時,,又時,滿足上式,因此,,

。

學(xué)科網(wǎng)(Zxxk.Com)15.解析:設(shè)正四面體的棱長為,連,取的中點,連,∵的中點,∴,∴或其補角為所成角,∵,∴,∴,又∵,∴,∴所成角的余弦值為。

學(xué)科網(wǎng)(Zxxk.Com)16.解析:∵,∴,∵點的準線與軸的交點,由向量的加法法則及拋物線的對稱性可知,點為拋物線上關(guān)于軸對稱的兩點且做出圖形如右圖,其中為點到準線的距離,四邊形為菱形,∴,∴,∴,∴,∴,∴向量的夾角為。

17.(10分)解析:(Ⅰ)由正弦定理得,,…2分

,,………4分

(Ⅱ)∵,,∴,∴,………………………6分

又∵,∴,∴,………………………8分

!10分

18.解析:(Ⅰ)∵,∴;……………………理3文4分

(Ⅱ)∵三科會考不合格的概率均為,∴學(xué)生甲不能拿到高中畢業(yè)證的概率;……………………理6文8分

(Ⅲ)∵每科得A,B的概率分別為,∴學(xué)生甲被評為三好學(xué)生的概率為!12分

(理)∵,,!9分

的分布列如下表:

0

1

2

3

的數(shù)學(xué)期望!12分

19.(12分)解析:(Ⅰ)時,

,,

    

得,   ………3分

 

 

+

0

0

+

遞增

極大值

遞減

極小值

遞增

      ………………………6分

(Ⅱ)在定義域上是增函數(shù),

恒成立,即 

   ………………………9分

(當且僅當時,

               

 ………………………4分

學(xué)科網(wǎng)(Zxxk.Com)              

20.解析:(Ⅰ)∵,,∴,∵底面,∴,∴平面,∴,又∵平面,∴,∴平面,∴!4分

(Ⅱ)∵平面,∴,∴為二面角的平面角,………………………6分

,,∴,又∵平面,,∴,∴二面角的正切值的大小為!8分

(Ⅲ)過點,交于點,∵平面,∴在平面內(nèi)的射影,∴與平面所成的角,………………………10分

學(xué)科網(wǎng)(Zxxk.Com),∴,又∵,∴與平面所成的角相等,∴與平面所成角的正切值為!12分

解法2:如圖建立空間直角坐標系,(Ⅰ)∵,,∴點的坐標分別是,,,∴,,設(shè),∵平面,∴,∴,取,∴,∴!4分

(Ⅱ)設(shè)二面角的大小為,∵平面的法向量是,平面的法向量是,∴,∴,∴二面角的正切值的大小為!8分

(Ⅲ)設(shè)與平面所成角的大小為,∵平面的法向量是,,∴,∴,∴與平面所成角的正切值為!12分

21.(Ⅰ) 解析:如圖,設(shè)右準線軸的交點為,過點


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