8．设是展开式的中间项.若在区间上恒成立.则实数的取值范围是——青夏教育精英家教网—

8．设是展开式的中间项.若在区间上恒成立.则实数的取值范围是【查看更多】

汉译英。

1. 据报道，那种疾病已经在全市扩散开来。(spread)
    _________________________________________________________________
2. 我们都知道他不诚实。(it's known to sb.)
    _________________________________________________________________
3. 说实话，他是个靠得住的人。(depend on)
    _________________________________________________________________
4. 众所周知，污染的空气和水对我们的身体是有害的。(harmful)
    _________________________________________________________________
5. 他们在月球上的感觉和在地球上听说的完全不一样。(be different from)
    _________________________________________________________________

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根据情景对话和内容，从对话后所给的选项中选出能填入空白处的最佳选项，并在答题卡上将该选项涂黑。注意：若选E为答案是，则在答题卡上选涂A和B两选；若选F为答案时，则在答题卡上选涂A和C两项；若选G为答案时，则在答题卡上选涂A和D两项。

---Hello. Can I speak to Wu Min, please?

---______6_______

---Hello, Wu Min. This is Wang Hong. Sorry to ring you so late in the evening, but I’ve only just got home.

---______7______ What can I do for you?

---I’d like to ask you about some stamps. Do you still have the cock year stamp? You had it when I last saw you.

---I’m afraid I don’t have it. I sold it last week.

---_____8_______

---I’m sorry. I didn’t know you wanted it. ____9______

---Yes, please. Thank you. It’s very kind of you.

---______10_______

---Thank you very much.

---Bye-bye.

A．Do you like collecting stamps so much?

B．That’s all right.

C．Sorry, Wu Min is out.

D．Do you want me to find one for you?

E.Oh, what a pity!

F.Yes, speaking.

G.OK, I’ll ring you if I have any news.

查看答案和解析>>

根据情景对话和内容，从对话后所给的选项中选出能填入空白处的最佳选项，并在答题卡上将该选项涂黑。注意：若选E为答案是，则在答题卡上选涂A和B两选；若选F为答案时，则在答题卡上选涂A和C两项；若选G为答案时，则在答题卡上选涂A和D两项。

---Hello. Can I speak to Wu Min, please?

---_____1._______

---Hello, Wu Min. This is Wang Hong. Sorry to ring you so late in the evening, but I’ve only just got home.

---_____2.______ What can I do for you?

---I’d like to ask you about some stamps. Do you still have the cock year stamp? You had it when I last saw you.

---I’m afraid I don’t have it. I sold it last week.

---____3.______

---I’m sorry. I didn’t know you wanted it. __4._____

---Yes, please. Thank you. It’s very kind of you.

---____5.______

---Thank you very much.

---Bye-bye.

A. Do you like collecting stamps so much

B. That’s all right.

C. Sorry, Wu Min is out.

D. Do you want me to find one for you?

E. Oh, what a pity!

F. Yes, speaking.

G. OK, I’ll ring you if I have any news.

查看答案和解析>>

根据情景对话和内容，从对话后所给的选项中选出能填入空白处的最佳选项，并在答题卡上将该选项涂黑。注意：若选E为答案是，则在答题卡上选涂A和B两选；若选F为答案时，则在答题卡上选涂A和C两项；若选G为答案时，则在答题卡上选涂A和D两项。

---Hello. Can I speak to Wu Min, please?

---______6_______

---Hello, Wu Min. This is Wang Hong. Sorry to ring you so late in the evening, but I’ve only just got home.

---______7______ What can I do for you?

---I’d like to ask you about some stamps. Do you still have the cock year stamp? You had it when I last saw you.

---I’m afraid I don’t have it. I sold it last week.

---_____8_______

---I’m sorry. I didn’t know you wanted it. ____9______

---Yes, please. Thank you. It’s very kind of you.

---______10_______

---Thank you very much.

---Bye-bye.

A.Do you like collecting stamps so much?

B.That’s all right.

C.Sorry, Wu Min is out.

D.Do you want me to find one for you?

E.Oh, what a pity!

F.Yes, speaking.

G.OK, I’ll ring you if I have any news.

查看答案和解析>>

根据情景对话和内容，从对话后所给的选项中选出能填入空白处的最佳选项，并在答题卡上将该选项涂黑。注意：若选E为答案是，则在答题卡上选涂A和B两选；若选F为答案时，则在答题卡上选涂A和C两项；若选G为答案时，则在答题卡上选涂A和D两项。

---Hello. Can I speak to Wu Min, please?

---______6_______

---Hello, Wu Min. This is Wang Hong. Sorry to ring you so late in the evening, but I’ve only just got home.

---______7______ What can I do for you?

---I’d like to ask you about some stamps. Do you still have the cock year stamp? You had it when I last saw you.

---I’m afraid I don’t have it. I sold it last week.

---_____8_______

---I’m sorry. I didn’t know you wanted it. ____9______

---Yes, please. Thank you. It’s very kind of you.

---______10_______

---Thank you very much.

---Bye-bye.

A.Do you like collecting stamps so much?

B.That’s all right.

C.Sorry, Wu Min is out.

D.Do you want me to find one for you?

E.Oh, what a pity!

F.Yes, speaking.

G.OK, I’ll ring you if I have any news.

查看答案和解析>>

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，若与共线，则与共线；若与共线，则，即，得，∴与共线，∴与共线是与共线的充要条件，故选C。

5．解析：设公差为，由题意得，；，解得或，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，又因为函数在是增函数，∴，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当或时，圆面被分成2块，涂色方法有20种；②当或时，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，∵为的中点，∴∥，∴或其补角为与所成角，∵，，∴，∴，又∵，∴，∴与所成角的余弦值为。

学科网(Zxxk.Com) 16．解析：∵，∴，∵点为的准线与轴的交点，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，∴，∴，∴，∴，∴，∴向量与的夹角为。

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，

，，

由得，或 ………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，

对恒成立，即

………………………9分

又（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）过点做∥，交于点，∵平面，∴为在平面内的射影，∴为与平面所成的角，………………………10分

学科网(Zxxk.Com) ∵，∴，又∵∥，∴和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，设右准线与轴的交点为，过点

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