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问题 解答题
已知集合A={x|x2-（2a+1）x+a（a+1）≤0}，B={x|
2x-1
x+2
≤1}，当A∩B=A时，求实数a的取值范围．
答案

A=x|（x-a）（x-a-1）≤0，

∵a＜a+1，

∴A=[a，a+1]（4分）

B={x|

2x-1
x+2
≤1}=(-2，3]（8分）

∵A∩B=A，∴A⊆B，∴

a＞-2
a+1≤3
，（12分）

解之得-2＜a≤2，

所以实数a的取值范围是（-2，2]．（14分）

完形填空

Dear Peter,

But first, I am sure that you are wrong that nobody will care if you leave your home. What about your parents? And other family members? It seems that you are very sad. You'd better go to see a doctor or talk to your parents. They can help you. Second, I'm sure there's someone in your class who feels lonely, too. You never know how other people feel inside. Try to make friends with them. Or you join a club to meet new people and to keep yourself busy.

You need to find happiness in yourself. Write a list of all the good things about yourself. Learn to like yourself, and then others will see your confidence (信心) and like you, too.

Editor

小题1:Peter isn’t good at _______ and he feels __________.

小题2:He writes to the editor to ask for _______ because he wants to _______feeling lonely.

小题3:If Peter joins a club, he can_______ new people and keep _______ busy.

小题4:The editor suggests (建议) that Tom should talk to a ________ and his ________.

小题5:Peter is lack of (缺少) _______ and he needs to find ________ in himself.
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