设椭圆
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231010860640668/SYS201311012310108606406019_ST/0.png)
的离心率
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231010860640668/SYS201311012310108606406019_ST/1.png)
,右焦点到直线
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231010860640668/SYS201311012310108606406019_ST/2.png)
的距离
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231010860640668/SYS201311012310108606406019_ST/3.png)
,O为坐标原点.
(I)求椭圆C的方程;
(II)过点O作两条互相垂直的射线,与椭圆C分别交于A,B两点,证明点O到直线AB的距离为定值,并求弦AB长度的最小值.
考点分析:
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