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问题 解答题
把下列各式分解因式：
（1）x3y-xy3；
（2）（x2+1）2-4x2；
（3）先化简再求值，
x-y
x
÷(x-
2xy-y2
x
)．其中x=2009，y=2010．
答案

（1）原式=xy（x2-y2）

=xy（x+y）（x-y）；

（2）原式=（x2+1-2x）（x2+1+2x）

=（x-1）2（x+1）2；

（3）原式=

x-y
x
÷
(x-y)2
x

=

x-y
x
×
x
(x-y)2

=

1
x-y
，

当x=2009，y=2010时，原式=

1
2009-2010
=-1．

完形填空

Complete the following passage by filling in each blank with one word that best fits the context.

The global financial crisis has contributed to   小题1: more fierce competition in job markets. College graduates are finding themselves in a situation   小题2: too many job seekers are fighting for survival. Our class has had a heated discussion on this problem.

Some think that   小题3:  makes sense that they realize an early employment by lowering their income expectations. They also believe there are better opportunities for development   小题4: they go to work in the west or rural areas. Others consider full employment an unrealistic goal,   小题5:   they choose to continue their further study   小题6: go to vocational schools to learn some practical skills to make better preparations for future careers.

As   小题7: me, I am confident and capable of overcoming the current difficulties and challenges after a series of timely measures taken by the government. All I need to do is make sure   小题8:  I can make full use of our talent and skills.
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单项选择题

下列叙述错误的是（）

A.古希腊哲学家亚里士多德认为物体越重，下落得越快

B.伽利略发现亚里士多德的观点有自相矛盾的地方

C.伽利略认为，如果没有空气阻力，重物与轻物应该下落得同样快

D.伽利略用实验直接证实了自由落体运动是初速度为零的匀加速直线运动
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