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已知△ABC中,a,b,c分别为角A,B,C的对边,,则∠B等于( ) A.60...
已知△ABC中,a,b,c分别为角A,B,C的对边,
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,则∠B等于( )
A.60°
B.30°或150°
C.60°
D.60°或120°
考点分析:
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D.
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