椭圆x225+y29=1上一点P到两焦点的距离之积为m，则m取最大值时P点坐标是( )

题干

椭圆25

x

2

+

y

2

9

=1上一点P到两焦点的距离之积为m，则m取最大值时P点坐标是( )

A：(0，3)或(0，－3)

B： $(\frac{5}{2}, \frac{3 \sqrt{3}}{2})$ 或 $(\frac{5}{2}, - \frac{3 \sqrt{3}}{2})$

C：(5，0)或(－5，0)

D： $(\frac{5 \sqrt{3}}{2}, \frac{3}{2})$ 或 $(- \frac{5 \sqrt{3}}{2}, \frac{3}{2})$

上一题下一题 0.0难度选择题更新时间:2017-11-10 09:03:41

A

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