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已知F1、F2分别是双曲线(a>0,b>0)的左、右焦点,P为双曲线上的一点,若...
已知F
1、F
2分别是双曲线
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104358062/SYS201310241826461043580009_ST/0.png)
(a>0,b>0)的左、右焦点,P为双曲线上的一点,若∠F
1PF
2=90°,且△F
1PF
2的三边长成等差数列,则双曲线的离心率是( )
A.2
B.3
C.4
D.5
考点分析:
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