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问题: 高一数学

化简
sin(x+60)+2in(x-60)-√3cos(120-x)
括号中数字指角度

解答:

化简
sin(x+60)+sin(x-60)-√3cos(120-x)
= sin(x+60)+sin(x-60)+√3cos(60+x)
=2sin(x+60+60)+sin(x-60)
=2sin(60-x)+sin(x-60)
=sin(60-x).

如果sin(x+60)+2sin(x-60)-√3cos(120-x)
= sin(x+60)+2sin(x-60)+√3cos(60+x)
=2sin(x+60+60)+2sin(x-60)
=2sin(60-x)+2sin(x-60)
=0.