sin(x+π/3)-√3cos(2π/3-x)+2sin(x-π/3)=sin(x+π/3)+√3cos(x+π/3)+2sin(x-π/3)=2(sin(x+π/3)cosπ/3+cos(x+π/3)sinπ/3)+2sin(x-π/3)=2sin(x+π/3+π/3)-2sin(x-π/3+π)=2sin(x+2π/3)-2sin(x+2π/3)=0