求y等于cos^2（2x-π/3）的导数.

题目

求y等于cos^2（2x-π/3）的导数.

答案

y=cos²(2x-π/3)
=[cos(4x-2π/3)+1]/2
=(1/2)cos(4x-2π/3)+1/2
y'=-(1/2)sin(4x-2π/3)*4
=-2sin(4x-2π/3)