14已知数列的前项和比集合的子集个数少1.则 . 查看更多

 

题目列表(包括答案和解析)

请根据A至F各课程的介绍和个各人的情况说明,选出符合各人要求的最佳选项。

A.You’ll be ready for the heated competition in the Nike Money Mesh Women’s Basketball Pants, a ventilated (透气的)design that offers a wide range of motion.
B.Be your own avatar(。。。) in the Nike “Your Head” Women’s T-shirt, a playful design that works hard to keep sweat at bay. It uses a Dri-FIT fabric to keep sweat away to help keep you dry and comfortable.
C.It is our classic cotton skirt, sweetened with lace (花边) at the edge. Waistband adjusts inside for a perfect fit. Jersey undershorts are attached. Just the perfect one for toddler girls aged 2-4.
D.If you want jeans with a skinny fit, or need something to fit well if you are skinny, come here! LV skinny 511 jeans. The jeans sit below the waist, with slim legs to the ankles. The jeans are our slimmest fit.
E. The Nike Air Jordan VI Retro basketball shoes will always be remembered as the sneakers that Michael wore while winning his first NBA championship. They were designed by the legendary Tinker Hatfield, and feature many fresh design elements.
F. Two jackets in one! That’s right! Adidas All-star NBA Men’s Jacket is reversible(可两面穿的)with front welt pockets. This jacket has a classic, full-front zip and hood with colorful artistry, which is 100% Adidas.
阅读以下人物的信息,然后匹配相应的服装:
46. Mary’s friend has invited her to attend a birthday party. She has asked her mom to buy a new pair of jeans for the party. She is a slim teen girl. Wearing jeans with slim legs may help her look tall and slim.
47. Jenny is going to Illinois to visit her old classmate Kate who is now a mother of a 3-year-old girl. She is looking for a gift for the little girl. She has decided to buy a lovely skirt for her. It must be very comfortable and made of cotton.
48. John is going for a camp this weekend,  but he can’t find a suitable jacket to keep warm outside and inside. So he would like to buy a new one. He wants to try something new that can be turned inside out and still be worn. In this way, he would not have to take too many things.
49. After suffering from a bad cold for a long time, Alice was advised to take exercise by her doctor. She wants to buy a T-shirt which can keep sweat away.  The T-shirt should be comfortable and keep her dry while she’s playing sports.
50. Lily’s company is going to have a basketball match and there is no doubt that Lily will be the front player. She’s looking for new sporting basketball pants and she’s a crazy Nike fan.

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下面是一篇应用文及其应用场合的信息,请阅读下列应用文和相关信息,并按照要求匹配信息。
请根据A至F各课程的介绍和个各人的情况说明,选出符合各人要求的最佳选项。
A. A Look at American Literature
A Look at American Literature is a course which gives us a brief outline of American Literature.
B. Works of Some Famous American Writers
Works of Some Famous American Writers show us the introductions to eleven famous writers and their works and also give us some comments on the works.
C. Detailed Reading of American Literature
Detailed Reading of American Literature is a course which focuses on some important and moving details in the works of American literature. It will analyse the detail.
D. Story and Plot
It’s a course which analyses the setting of the main plots in some famous stories. The aim of this course is to help those who want to become writers in the future.
E. Characters and Life
As you know, literature comes from our life, but it’s more than our life. This course will analyze the personalities of some important characters in the world literature, and combine the analysis with our life. It will help us gain wisdom from the characters.
F. Literature Comments
The course is a study of how to write literature comments through some vivid examples.
请阅读以下学生的相关信息,然后匹配他/她和拟要选择的课:
Helen wants to become a famous writer in the future. She is eager to take a course which can help her realize her dream.
Peter was ill last term and missed a lot of lessons in American literature. He wants to take a course which can give him an outline of it.
Kate likes to read literature works and she has many opinions after reading, but she doesn’t know how to express her ideas properly.
Tommy has the basic knowledge of American literature. He wants to take a course which can help him read more famous works about American literature.
Jerry wants to write some articles to show the significance of researching literature today. He is looking for a course which can help him.
待选课程学生                        课程名称
【小题1】 Helen              A.  A Look at American Literature
【小题2】Peter               B.  Works of Some Famous American Writers
【小题3】 Kate               C.  Detailed Reading of American Literature
【小题4】 Tommy              D.  Story and Plot
【小题5】Jerry               E.  Characters and Life
F.  Literature Comments

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根据所给的中文和括号内的语法提示, 把下面句子翻译成英语,写在答题卷相应的横线上。
【小题1】 我觉得很奇怪他睡得那么少却能够干得那么卖力。(宾语从句)
I find ______ ________ ______ he is able to work so hard with so little sleep.
【小题2】 这两姐妹一定是吵架了,因为她们互不理睬。(must have done)
The sisters _______ _______ _______ an argument, for they are no longer talking to each other.
【小题3】 那位老师和两个学生参加了会议。(主谓一致)
The ________ with two ________ ________ at the meeting.
【小题4】 是什么事使他不能参加我们的会议仍然是个谜。(主语从句)
_______ prevented him from _______ our meeting still ______ a mystery.
【小题5】老师不用抬头看就已经知道是哪个学生在班上讲话。(V+ing 作宾语)
Without ______ ______ _______ her desk, the teacher already knew which student was talking in class.  

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根据句子的意思和括号里的中文提示以及首字母, 写出下列的单词。要求写出完整单词。
【小题1】 The Greek financial difficulties would not be easily o________(战胜).
【小题2】The single mother is s________(奋力) to bring up her child alone.
【小题3】 We all i________(打算)to have DIY decorations, but our cupboards will be made by a carpenter.
【小题4】The new credit cards will be of great b________(利益) to our customers.
【小题5】 Most of the compositions written by the students were very good i___________(真正地).
【小题6】 I can say to the governor that he ___________ (误解)the order and tried to defend himself.
【小题7】 He was a little boy, but he ___________(行为表现)as if he was an adult.
【小题8】The government’s actions are ___________(相违的)to the public interest.
【小题9】___________(不像)most people in the office, I don’t come to work by car.
【小题10】He created a new ___________(体系)of teaching foreign languages.

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完成句子(共14空,每空0.5分,满分7分)
【小题1】你只有在不远离河岸的条件下才能去游泳。
You can go swimming               that you don’t go too far from the river bank.
【小题2】他被委任承担学校各方面的管理工作。
He has been        to        the school management in all respects.
【小题3】写一篇名为音乐的回忆的文章,字数不限。
Write an essay of as many words as you like        the        of “Musical Memories”.
【小题4】幸福不在于拥有很多,而在于就算拥有很少也很满足。
Happiness        not in having much, but in being        with little.
【小题5】麦克很谦虚,他把他的成功都归功于他的父母和老师们。
Mike is modest and he        a lot of his success        his parents and teachers.
【小题6】据报道中国的经济总量目前仅次于美国——比日本或欧洲任何一个国家都要大。
It is reported that China’s economy is now               to the United States, larger than that of Japan or any single member of the European Union.
【小题7】在上世纪90年代,他来到深圳,寻求成功的机会。
In the 1990’s, he came to Shenzhen to        his       

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1.解析:,故选A。

2.解析:∵

故选B。

3.解析:由,得,此时,所以,,故选C。

4.解析:显然,若共线,则共线;若共线,则,即,得,∴共线,∴共线是共线的充要条件,故选C。

5.解析:设公差为,由题意得,,解得,故选C。

6.解析:∵双曲线的右焦点到一条渐近线的距离等于焦距的,∴,又∵,∴,∴,∴双曲线的离心率是。故选B.

7.解析:∵为正实数,∴,∴;由均值不等式得恒成立,,故②不恒成立,又因为函数是增函数,∴,故恒成立的不等式是①③④。故选C.

8.解析:∵,∴在区间上恒成立,即在区间上恒成立,∴,故选D。

9.解析:∵

,此函数的最小值为,故选C。

10.解析:如图,∵正三角形的边长为,∴,∴,又∵,∴,故选D。

11.解析:∵在区间上是增函数且,∴其反函数在区间上是增函数,∴,故选A

12.解析:如图,①当时,圆面被分成2块,涂色方法有20种;②当时,圆面被分成3块,涂色方法有60种;

③当时,圆面被分成4块,涂色方法有120种,所以m的取值范围是,故选A。

13.解析:做出表示的平面区域如图,当直线经过点时,取得最大值5。

学科网(Zxxk.Com)14.解析:∵,∴时,,又时,满足上式,因此,

学科网(Zxxk.Com)15.解析:设正四面体的棱长为,连,取的中点,连,∵的中点,∴,∴或其补角为所成角,∵,∴,∴,又∵,∴,∴所成角的余弦值为

学科网(Zxxk.Com)16.解析:∵,∴,∵点的准线与轴的交点,由向量的加法法则及抛物线的对称性可知,点为抛物线上关于轴对称的两点且做出图形如右图,其中为点到准线的距离,四边形为菱形,∴,∴,∴,∴,∴,∴向量的夹角为

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)∵三科会考不合格的概率均为,∴学生甲不能拿到高中毕业证的概率;……………………理6文8分

(Ⅲ)∵每科得A,B的概率分别为,∴学生甲被评为三好学生的概率为。……………………12分

(理)∵。……………………9分

的分布列如下表:

0

1

2

3

的数学期望。……………………12分

19.(12分)解析:(Ⅰ)时,

    

得,   ………3分

 

 

+

0

0

+

递增

极大值

递减

极小值

递增

      ………………………6分

(Ⅱ)在定义域上是增函数,

恒成立,即 

   ………………………9分

(当且仅当时,

               

 ………………………4分

学科网(Zxxk.Com)              

20.解析:(Ⅰ)∵,∴,∵底面,∴,∴平面,∴,又∵平面,∴,∴平面,∴。………………………4分

(Ⅱ)∵平面,∴,∴为二面角的平面角,………………………6分

,∴,又∵平面,∴,∴二面角的正切值的大小为。………………………8分

(Ⅲ)过点,交于点,∵平面,∴在平面内的射影,∴与平面所成的角,………………………10分

学科网(Zxxk.Com),∴,又∵,∴与平面所成的角相等,∴与平面所成角的正切值为。………………………12分

解法2:如图建立空间直角坐标系,(Ⅰ)∵,,∴点的坐标分别是,∴,设,∵平面,∴,∴,取,∴,∴。………………………4分

(Ⅱ)设二面角的大小为,∵平面的法向量是,平面的法向量是,∴,∴,∴二面角的正切值的大小为。………………………8分

(Ⅲ)设与平面所成角的大小为,∵平面的法向量是,∴,∴,∴与平面所成角的正切值为。………………………12分

21.(Ⅰ) 解析:如图,设右准线轴的交点为,过点


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