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命题:“∀x∈R,cos2x≤cos2x”的否定为( ) A.∀x∈R,cos2...
命题:“∀x∈R,cos2x≤cos2x”的否定为( )
A.∀x∈R,cos2x>cos2
B.∃x∈R,cos2x>cos2
C.∀x∈R,cos2x<cos2
D.∃x∈R,cos2x≤cos2
考点分析:
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