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问题 选择题

设函数f(x)＝xex，则(　　)

A．x＝1为f(x)的极大值点

B．x＝1为f(x)的极小值点

C．x＝－1为f(x)的极大值点

D．x＝－1为f(x)的极小值点

答案

答案：D

题目分析：，令得，令得，所以在上单调递减，在上单调递增。所以为的极小值点。故D正确。

选择题
下列词语中划线字的注音和字形完全正确的一项是
[ ]
A．留滞（zhì）牧场（mù）斗笠（lì）襁褓（qiáng）
B．耸立（sǒng）踪迹（jì）谙哑（yīn）喧嚷（rǎng）
C．油膏（gāo）丝缕（lǚ）禁锢（gù）蓑衣（suō）
D．田圃（bǔ）乳名（rǔ）跳跃（yuè）新编（biān）
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完形填空

I am going to tell you an unbelievable story. This afternoon a __41___(poor)  dressed gentleman came into my restaurant. Nobody knew who he was and __42___he came from. After __43___(sit) down, he ordered a lot of food. He stared at it and then _44___ (eat) it up very quickly.

To be_45___, we doubted whether the man was able to pay for the food. When he was asked to pay the bill, the gentleman asked if we would mind__46__ (wait) just a few minutes. Then we were _47___ (shock) to see that he took a million pound bank note. __48__(fortunate), we could not change the bank note as it was too large. So I gave this strange but very rich man a _49__ dinner, in the hope__50__he might come to our restaurant again.
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