题干

小刚同学动手剪了如图①所示的正方形与长方形纸片若干张.观察与操作:

(1)他拼成如图②所示的正方形,根据四个小纸片的面积之和等于大正方形的面积,得到:a2+2ab+b2=(a+b)2,验证了完全平方公式;即:多项式  a2+2ab+b2分解因式后,其结果表示正方形的长(a+b)与宽(a+b)两个整式的积.
(2)当他拼成如图③所示的矩形,由面积相等又得到:a2+3ab+2b2=(a+2b)(a+b),即:多项式 a2+3ab+2b2分解因式后,其结果表示矩形的长(a+2b)与宽(a+b)两个整式的积.
问题解决:
(1)请你依照小刚的方法,利用拼图写出恒等式a2+4ab+3b2.(画图说明,并写出其结果)
(2)试猜想面积是2a2+5ab+3b2的矩形,其长与宽分别是多少?(画图说明,并写出其结果)

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    A new generation addiction is quickly spreading all over the world. Weboholism, a twentieth century disease, affects people from different ages. They surf the net, use email and speak in chat rooms. They spend many hours on the computer, and it becomes a compulsive habit. They cannot stop, and it affects their lives.

    Ten years ago, no one thought that using computers could become compulsive behavior that could affect the social and physical life of computer users. This obsessional behavior has affected teenagers and college students. They are likely to log on computers and spend long hours at different websites.

    They become hooked on computers and gradually their social and school life is affected by this situation. They spend all free time surfing and don't concentrate on homework, so this addiction influences their grades and success at school. Because they can find everything on the websites, they hang out there. Moreover, this addiction to websites influences their social life.

    They spend more time in front of computers than with their friends. The relation with their friends changes. The virtual life becomes more important than their real life. They have a new language that they speak in the chat rooms and it causes cultural changes in society.

    Because of the change in their behavior, they begin to isolate themselves from the society and live with their virtual friends. They share their emotions and feelings with friends who they have never met in their life. Although they feel confident on the computer, they are not confident with real live friends they have known all their life. It is a problem for the future. This addictive behavior is beginning to affect all the world.