y=sinx图象怎么变成cos(2x-π/6)的图象.
问题描述：
y=sinx图象怎么变成cos(2x-π/6)的图象.
答
y=cos(2x-π/6)
=cos(π/6-2x)
=sin[π/2-(π/6-2x)]
=sin(2x+π/3)
=sin[2(x+π/6)]
所以向左移π/6
然后把横坐标缩小为原来的1/2