f(x)=sin (2x-π/4)可以写成f(x)=cos(2x+π/4)

问题描述:

f(x)=sin (2x-π/4)可以写成f(x)=cos(2x+π/4)

不可以的
f(x)=sin (2x-π/4)
=-cos[π/2+(2x-π/4)]
=-cos(2x+π/4)