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己知命题“∃x∈R,2x2+(a-1)x+≤0是假命题,则实数a的取值范围是( ...
己知命题“∃x∈R,2x
2+(a-1)x+
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≤0是假命题,则实数a的取值范围是( )
A.(-∞,-1)
B.(-1,3)
C.(-3,+∞)
D.(-3,1)
考点分析:
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A.a<c<b
B.a<b<c
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D.c<a<b
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