设椭圆的两个焦点分别为 F1,F2 ，过 F2 作椭圆长轴的垂线交椭圆于点 P ，若△ F1PF2 为等腰直角三角形，则椭圆的离心率是_刷题宝

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设椭圆的两个焦点分别为 F1,F2 ，过 F2 作椭圆长轴的垂线交椭圆于点 P ，若△ F1PF2 为等腰直角三角形，则椭圆的离心率是（）

A： $\frac{\sqrt{2}}{2}$

B： $\frac{\sqrt{2} - 1}{2}$

C： $2 - \sqrt{2}$

D： $\sqrt{2} - 1$

上一题下一题 0.0难度选择题更新时间:2016-03-02 03:47:27

答案(点此获取答案解析）

D

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