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命题“∀x∈R,x2-2x+4≤0”的否定为( ) A.∀x∈R,x2-2x+4...
命题“∀x∈R,x2-2x+4≤0”的否定为( )
A.∀x∈R,x2-2x+4≥0
B.∀x∉R,x2-2x+4≤0
C.∃x∈R,x2-2x+4>0
D.∃x∉R,x2-2x+4>0
考点分析:
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