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圆内接正方形的面积为a,则圆的面积为( ) A.2πa B. C. D.以上都不...
圆内接正方形的面积为a,则圆的面积为( )
A.2πa
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103102458338821909/SYS201311031024583388219005_ST/0.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103102458338821909/SYS201311031024583388219005_ST/1.png)
D.以上都不对
考点分析:
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