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问题 填空题

方程y2=x2+2006的正整数解的个数是 ______．

答案

∵求y2=x2+2006的正整数解，

y2-x2=2006

显然x、y＞0，y＞xy2-x2=（x+y）（y-x）=2006=2×1003因（x+y）、（y-x）奇偶性相同，又因2006含偶因数．所以（y+x）、（y-x）必同偶．而y2-x2只能分解成一个奇数和一个偶数，所以找不到这样的一组数据．

故答案为：0

单项选择题 A1型题

职权从组织上层“流向”组织基层，属于以下哪种组织结构（）。

A.直线型

B.综合型

C.主导型

D.职能型

E.直线-参谋型
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补全对话，情景问答

根据所给情景，从A、B、C三个选项中选出最佳选项。

1. — Can I take this seat?

    — _______. It's for our teacher, Mr Li. [ ]

A. Of course

B. You'd better not

C. Yes, please

2. — You speak English well.

    — _______. [ ]

A. Don't say so

B. Just so-so

C. Thank you

3. — There's going to be an exciting basketball match in our school.

    — _______ I can't wait. [ ]

A. It's boring.

B. What a pity!

C. That's great.

4. — I have to make a speech at a meeting. I feel nervous about it.

    — _______. I'm sure you can do it well. [ ]

A. Take it easy

B. Don't be so sad

C. That's all right

5. — What do you think of the math problem?

    — _______. All of us can work it out. [ ]

A. It's a piece of cake

B. It's difficult

C. I hope so

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