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“∃x∈R,x2+ax-2a<0为假命题”是“-8≤a≤0”的( ) A.充要条...
“∃x∈R,x2+ax-2a<0为假命题”是“-8≤a≤0”的( )
A.充要条件
B.必要不充分条件
C.充分不必要条件
D.既不充分也不必要条件
考点分析:
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B.
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C.
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D.
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已知向量
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=(cosα,sinα),
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∥
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,则tanα=( )
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C.2
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