Question

1+cosx-cosx/2=0 помогите пожалуйста

Answer 1

1+cosx -cos(x/2) =0 ;
2cos²(x/2) - cos(x/2) =0 ;
2cos(x/2)*( cos(x/2) -1/2) =0 ;
[ cos(x/2)=0 ; cos(x/2) -1/2 =0⇒[x/2  =π/2 +πn ; x/2  =(+/-)π/3 +2πn ,n∈Z.

[ x  =π +2πn ; x  =(+/-)2π/3 +4πn ,n∈Z.