求函数f(x)=2sin^2x +cos(x +π/3)单调增区间
问题描述:
求函数f(x)=2sin^2x +cos(x +π/3)单调增区间
开头是sinx平方的二倍
把步骤写清楚具体点 (把要点点出来)
答
f(x)=cos(2x-π/3)+2sin(x-π/4)sin(x+π/4)f(x)=1/2cos 2x+√3/2sin 2x+2(sin x-cos x)(xin x+cos x)=1/2cos 2x+√3/2sin 2x-2(cos^2 x-sin^2 x)=1/2cos 2x+√3/2sin 2x-2cos 2x=-3/2cos 2x+√3/2sin 2x=√3(1/2sin...