cos(5π/3-x)+cosx = cos5π/3· cosx + sin5π/3·sinx + cosx = 0.5 cosx - 0.5√3·sinx + cosx=
= 1.5cosx - 0.5√3·sinx
cos(5π/3-x)+cosx = cos5π/3· cosx + sin5π/3·sinx + cosx = 0.5 cosx - 0.5√3·sinx + cosx=
= 1.5cosx - 0.5√3·sinx