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已知F为椭圆的右焦点,点P(1,m)在C上,且PF⊥x轴,椭圆C的离心率为. (1)求椭圆C的方程; (2)若直线l:y=kx+2与椭圆C相交于A,B两点,且(O为坐标原点),求k的取值范围.
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已知点F1F2是椭圆+=1a>b>0的左右焦点在此椭圆上存在点P.使∠F1PF2=60°且|PF1|
已知F1F2是椭圆的两个焦点P.是椭圆上一点且∠F1PF2=60°.1求椭圆离心率的取值范围2求证△
如图已知P.是椭圆+=1a>b>0上且位于第一象限的一点F.是椭圆的右焦点O.是椭圆中心B.是椭圆的
点A.B.分别是椭圆+=1长轴的左右端点点F.是椭圆的右焦点点P.在椭圆上且位于x轴上方PA⊥PF.
椭圆C.=1a>b>0的左右焦点分别是F.1F.2离心率为过F.1且垂直于x轴的直线被椭圆C.截得的
点A.B.分别是椭圆+=1长轴的左右端点点F.是椭圆的右焦点点P.在椭圆上且位于x轴上方PA⊥PF.
已知O为坐标原点F是椭圆C://的左焦点AB分别为C的左右顶点P为C上一点且PF⊥x轴过点A的直线
A
B
C
D
点AB分别是椭圆长轴的左右端点点F是椭圆的右焦点点P在椭圆上且位于x轴上方PA⊥PF 1求点P的坐
已知椭圆C.的中心在的点焦点在x轴上F1F2分别是椭圆C.的左右焦点M.是椭圆短轴的一个端点过F1的
已知F1F2是椭圆C.的左右焦点点P.在椭圆上且满足PF1=2PF2∠PF1F2=30°则椭圆的离心
已知A.B是椭圆的左右顶点过椭圆C的右焦点F的直线交椭圆于点MN交直线x=4于点P且直线PAPFPB
已知F1F2分别是椭圆C.的左右焦点点P.在椭圆上且满足PF1=2PF2∠PF1F2=30°则椭圆的
已知F1F2分别为椭圆=1a>b>0左右焦点点P1y0在椭圆上且PF2⊥x轴△PF1F2的周长为61
点AB分别是椭圆长轴的左右端点点F是椭圆的右焦点点P在椭圆上且位于x轴上方PA⊥PF1求点P的坐标2
已知F是椭圆的左焦点AB为椭圆C的左右顶点点P在椭圆C上且PF⊥x轴过点A的直线与线段PF交与点M
已知椭圆C.的中心在原点左焦点F1右焦点F2均在x轴上
为椭圆的右顶点,
为椭圆短轴的端点,P.是椭圆上一点,且PF
1
⊥x轴,PF
2
∥AB,则此椭圆的离心率等于 A.
B.
点A.B.分别为椭圆+=1长轴的左右端点点F.是椭圆的右焦点点P.在椭圆上且位于x轴上方PA⊥PF.
点AB分别是椭圆长轴的左右端点点F是椭圆的右焦点点P在椭圆上且位于x轴上方PA⊥PF 1求点P的坐
已知O为坐标原点F是椭圆C=1a>b>0的左焦点ABD分别为椭圆C的左右顶点和上顶点P为C上一点且
已知有公共焦点的椭圆与双曲线的中心为原点焦点在x轴上左右焦点分别为F.1F.2且它们在第一象限的交点
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