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给出以下命题:①∃x∈R,sinx+cosx>1②∀x∈R,x2-x+1>0③“...
给出以下命题:①∃x∈R,sinx+cosx>1②∀x∈R,x2-x+1>0③“x>1”是“|x|>1”的充分不必要条件,其中正确命题的个数是( )
A.0
B.1
C.2
D.3
考点分析:
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