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椭圆x2+my2=1的离心率为,则m的值为( ) A.2 B. C.2或 D.或...
椭圆x
2+my
2=1的离心率为
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100741640388373/SYS201311031007416403883002_ST/0.png)
,则m的值为( )
A.2
B.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100741640388373/SYS201311031007416403883002_ST/1.png)
C.2或
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100741640388373/SYS201311031007416403883002_ST/2.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100741640388373/SYS201311031007416403883002_ST/3.png)
或4
考点分析:
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