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已知α,β均为锐角,且cos(α+β)<0,则下列结论一定成立的是( ) A.c...
已知α,β均为锐角,且cos(α+β)<0,则下列结论一定成立的是( )
A.cosα>cosβ
B.sinα>sinβ
C.cosα>sinβ
D.sinα>cosβ
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