题干

如图是2002年8月在北京召开的国际数学家大会的会标,它取材于我国古代数学家赵爽的《勾股圆方图》,由四个全等的直角三角形和一个小正方形的拼成的大正方形,如果大正方形的面积是5,小正方形的面积是1,直角三角形的较短边为a,较长边为b,那么(a+b)2的值是(   )

A:4

B:9

C:16

D:25

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B

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    One of the most striking findings of a newly research in the UK is that of the people interviewed, one in two believes that it is becoming more difficult to meet someone to start a family with.

    Why are many finding it increasingly difficult to start close relationships? Does modem life really make it harder to fall in love? Or are we making it harder for ourselves? It is certainly the case today that contemporary couples benefit in different ways from relationships. Women no longer rely upon partners for money or status. A man doesn't expect his wife to be in (唯一的) charge of running his household and raising his children.

    But perhaps the knowledge that we can live perfectly well without a partnership means that it takes much more to persuade people to abandon their independence.

    In theory, finding a partner should be much simpler these days. Only a few generations ago, your choice of soul mate was limited by geography, social convention and family tradition. Although it was never clear,many marriages were essentially arranged. Now those barriers have been broken down. You can approach a builder or a brain surgeon in any bar in any city on any given evening. When the world is your oyster ( 牡蛎), you surely have a better chance of finding a pearl.

    But it seems that the old conventions have been replaced by the limitations of choice. The expectations of partners are raised to an unmanageable degree: good looks, impressive salary, kind to grandmother, and right socks. There is no room for error in the first impression.

    We think that a relationship can be perfect. If it isn't, it should be ended. We work to protect ourselves against future heartache and don't put in the hard emotional labor needed to build a strong relationship. Twelve-hour work at the office makes relaxed after-hours dating difficult. The cost of housing and child-raising creates pressure to have a stable income and Career before a life partnership.