已知椭圆的焦点是F1(0,-1),F2(0,1),离心率e=
.
(1)求椭圆的标准方程;
(2)设P在这个椭圆上且|PF1|-|PF2|=1,求∠F1PF2的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
(1)求椭圆的标准方程;
(2)设P在这个椭圆上且|PF1|-|PF2|=1,求∠F1PF2的余弦值.
更新时间:2020-10-15 18:51:04
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【推荐1】一道解三角形的题目有一个条件不清楚,具体如下:
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【推荐1】已知椭圆具有如下性质:若椭圆的方程为
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【推荐2】已知椭圆
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为“稳定点”,问:是否存在这样的稳定点?若有,试求出所有“稳定点”,并说明理由;若没有,也请说明理由.
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