f(x)=sinx+sin(x+2π/3)=simx+simxcos2π/3+cosxsin2π/3=sinx-1/2sinx+√3/2cosx=1/2sinx+√3/2cosx=sin(x+π/3)(1)∵T=2π,∴相邻两个对称轴之间的距离是π；(2)f(x)=1/3,即sin(x+π/3)=1/3,∴cos(2x+2π/3)=cos2(...