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lgx,lgy,lgz成等差数列是由y2=zx成立的( ) A.充分非必要条件 ...
lgx,lgy,lgz成等差数列是由y2=zx成立的( )
A.充分非必要条件
B.必要非充分条件
C.充要条件
D.既不充分也不必要条件
考点分析:
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给出计算
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的值的一个程序框图如图,其中判断框内应填入的条件是( )
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B.i<10
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已知离心率为e的曲线
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=1,其右焦点与抛物线y
2=16x的焦点重合,则e的值为( )
A.
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B.
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C.
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D.
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A.0个
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设数列{a
n}是等差数列,且a
2=-8,a
15=5,S
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已知向量
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∥
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,则x=( )
A.2
B.-2
C.8
D.-8
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