sin(x/3)cos(x/3）+√3cos^2(x/3)=(1/2)sin(2x/3)+(√3/2)[1+cos(2x/3)]=(1/2)sin(2x/3)+(√3/2)cos(2x/3)+√3/2=sin(2x/3)cos(π/3)+cos(2x/3)sin(π/3)+√3/2=sin(2x/3+π/3)+√3/2