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(2002•益阳)已知圆内接正六边形的边长为a,半径为R,边心距为r,则a:R:...
(2002•益阳)已知圆内接正六边形的边长为a,半径为R,边心距为r,则a:R:r=( )
A.1:1:
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232550768788637/SYS201310212325507687886019_ST/0.png)
B.2:2:
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232550768788637/SYS201310212325507687886019_ST/1.png)
C.1:2:3
D.1:2:
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232550768788637/SYS201310212325507687886019_ST/2.png)
考点分析:
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