在△ABC中,已知(sinA+sinB+sinC)(sinB+sinC-sinA)=3sinBsinC.
(1)求角A的值;
(2)求
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的最大值.
考点分析:
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如图,在等腰三角形ABC中,已知AB=AC=1,A=120°,E,F分别是边AB,AC上的点,且
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,
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的最小值为
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若对满足条件x+y+3=xy(x>0,y>0)的任意x,y,(x+y)
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已知角φ的终边经过点P(1,-1),点A(x
1,y
1),B(x
2,y
2)是函数f(x)=sin(ωx+φ)(ω>0)图象上的任意两点,若|f(x
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的值是
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