在△ABC中,A、B、C、是三角形的三内角,a、b、c是三内角对应的三边,已知b
2+c
2-a
2=bc.
(Ⅰ)求角A的大小;
(Ⅱ)若sin
2A+sin
2B=sin
2C,求角B的大小.
考点分析:
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8的展开式中x
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