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“x>0”是“x≠0”的( ) A.充分而不必要条件 B.必要而不充分条件 C....
“x>0”是“x≠0”的( )
A.充分而不必要条件
B.必要而不充分条件
C.充分必要条件
D.既不充分也不必要条件
考点分析:
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的渐近线方程和离心率分别是( )
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C.
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A.f
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B.f
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C.f
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的焦点坐标是( )
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如图,已知P、O分别是正四棱柱ABCD-A
1B
1C
1D
1上、下底面的中心,E是AB的中点,AB=kAA
1,其中k为非零实数,
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