cos(2x+2π/3)+4sin(x+π/3)=5/2

Cos(2x +2π/3) = Cos2(x +π/3) = 1 - 2Sin²(x +π/3)Cos(2x+2π/3)+4Sin(x+π/3)=5/2,1 - 2Sin²(x +π/3)+4Sin(x+π/3)=5/2,Sin(x+π/3)=t,-2t² + 4t-1,5 = 04t² -8t +3 = 0t = (4+-√(16 -12)/4t₁ =6/4 = 1,5                       t₂=0,5Sin(x + π/3) = 1,5               Sin(x+π/3)=0,5,∅                                         x + π/3 = (-1)^n arcSin0,5 + nπ, n ∈Z                                           x + π/3 = (-1)^n* π/6 + nπ, n ∈ Z                                           x =  -π/3 = (-1)^n* π/6 + nπ, n ∈ Z