помогите
cosx + sin(1,5Пи + 2x)=0

cosX+sin(3π/2+2x)=0cosx-cos2x=0cosx-2cos²x+1=02cos²x-cosx-1=0D=9; √D=3cosx=-1/2x=+ - 2π/3+2πn, n € Zcosx=1x=2πn, n € Z