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问题 问答题

计算[*]，其中L是x2+y2=4x的上半圆周由A(4，0)至B(0，0)．

答案

参考答案：积分路线如图所示
[*]
∵P=y+2xy Q=x2+x+y2
[*]，故积分与路径无关
[*]

填空题

单词拼写

1. He got a job in a foreign company after g _____________(毕业) from university.

2. It is very difficult to p ______________(说服) my father to give up smoking.

3. All these goods will be t_________________(运输) abroad by ship.

4. She looks down upon those people b_______________ (在…下面)her.

5. According to the weather f____________(预报)it will rain tomorrow.

6. Sometimes whether you are a success is determined by the different a______________(态度)

7. The plane is now flying at an  a_______________(海拔)of 30 000 feet.

8．He seems to be doing nothing , but _____________ ( 实际上 ) he is just waiting for his chance.

9. He was c____________________ (骑自行车)along the street when he was knocked off his bike.

10. We all know that he is too ___________________(顽固) to apologize.
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判断题

对精制系统采用真空操作，能节省能源。（）
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