f(x)=2sin(x-π/3)cos(x-π/3)+2√3cos^2(x-π/3)-√3　　=sin(2x-2π/3)+√3cos(2x-2π/3)　　=2[sin(2x-2π/3)cosπ/3+cos(2x-2π/3sinπ/3]　　=2sin(2x-2π/3+π/3)+1-√3　　=2sin(2x-π/3)　　故 f(2x)-a=2sin...