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问题 填空题

若抛物线f（x）=x2+ax与直线f'（x）-1-y=0相切，则此切线方程为 ______．

答案

∵f（x）=x2+ax

∴f'（x）=2x+a

则f'（x）-1-y=0即2x-y+a-1=0

∵抛物线f（x）=x2+ax与直线f'（x）-1-y=0相切

∴

y=x2+ax
y=2x+a-1
即x2+（a-2）x+1-a=0只有一解

即△=（a-2）2-4（1-a）=0

解得a=0

∴此切线方程为2x-y-1=0

故答案为：2x-y-1=0

填空题

结合课文理解词语，并填空。

“可以预料，在本世纪，雅鲁藏布大峡谷必将成为世界人民关注的一个热点。”

“热点”在文中是指____________。你所在的城市，________、________也是旅游的热点。
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改错题
短文改错。
Have you ever suffered from some pains while grow up?
Don't worry. I'll tell you some possible ways to deal with it. 
If you have few friends because you are shyly, you 
may try to say hello to your classmates with smile
first and  start to talk with them first. Then you'll find
they are friendly but very easy to get along with.
To get good grades, you had to stop reading entertainment 
magazine, and try your best to learn your lessons well.
Believe on yourself, and you'll be successful. If you have any 
questions, and you can turn to your friends or teachers for help.

1. _____                                      
2. _____
3. _____
4. _____
5. _____
6. _____
7. _____
8. _____
9. _____
10. _____
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