Упростить выражение sin(п/3+а)+sin(п/3-а)
Sin(π/3+α)+sin(π/3-α)= =sin(π/3)·cosα+cos(π/3)·sinα+sin(π/3)·cosα-cos(π/3)·sinα= =2sin(π/3)·cosα=2·(√3/2)·cosα=√3·cosα;