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如图,正ABC中,P为正三角形内任意一点,过P作PD⊥BC、PE⊥AB,PF⊥A...
如图,正ABC中,P为正三角形内任意一点,过P作PD⊥BC、PE⊥AB,PF⊥AC,连AP、BP、CP,如果S
△AFP+S
△PCD+S
△BPE=
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164116915558097/SYS201310221641169155580008_ST/0.png)
,那么△ABC的内切圆半径为( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164116915558097/SYS201310221641169155580008_ST/images1.png)
A.1
B.
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C.2
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164116915558097/SYS201310221641169155580008_ST/2.png)
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D.2
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164116915558097/SYS201310221641169155580004_ST/5.png)
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D.
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