y=cos2x+sinx(sinx+cosx) 化简
问题描述:
y=cos2x+sinx(sinx+cosx) 化简
答
y=cos2x+sinx(sinx+cosx)
= cos2x + sin²x + sinxcosx
=cos2x +(1 - cos2x)/2 + sin2x/2
=0.5 + 0.5cos2x + 0.5sin2x
=0.5 + √2sin(2x + π/4)/2