函数y=sin(3x+π/3)cos(x-π/6)+cos(3x+π/3)cos(x+π/3)的图像的一条对称轴的方程是?

问题描述:

函数y=sin(3x+π/3)cos(x-π/6)+cos(3x+π/3)cos(x+π/3)的图像的一条对称轴的方程是?

cos(x+π/3)=sin(π/2-x-π/3)=sin(π/6-x)=-sin(x-π/6)y=sin(3x+π/3)cos(x-π/6)+cos(3x+π/3)cos(x+π/3)=sin(3x+π/3)cos(x-π/6)-cos(3x+π/3)sin(x-π/6)=sin(3x+π/3-x+π/6)=sin(...额不对!!哈哈你也错了答案是x=π/4!!!cos2x的对称轴为2x=kπx=kπ/2,k为整数选项D满足条件。