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在△ABC中,角A,B,C所对的边分别为a,b,c,S表示△ABC的面积,若ac...
在△ABC中,角A,B,C所对的边分别为a,b,c,S表示△ABC的面积,若acosB+bcosA=csinC,S=
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(b
2+c
2-a
2),则∠B=( )
A.90°
B.60°
C.45°
D.30°
考点分析:
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