f（x）=cos（wx+y）-sin（wx+y）化简
问题描述：
f（x）=cos（wx+y）-sin（wx+y）化简
答
f(x)=√2[(√2/2)cos(wx＋y)－(√2/2)sin(wx＋y)]
=√2[cos(wx＋y)cos(π/4)－sin(wx＋y)sin(π/4)]
=√2cos(wx＋y＋π/4)