Решите уравнение: (cos2x+cosx+1)/(2sinx+√3)=0

2sinx+√3≠0⇒sinx≠-√3/2⇒x≠-π/3+2πn,n∈z U x≠4π/3+2πn
cos2x+cosx+1=0
2cos²x-1+cos+1=0
2cos²x+cosx=0
cosx(2cosx+1)=0
cosx=0⇒x=π/2+πn,n∈z
2cosx+1=0
cosx=-1/2
x=2π/3+2πn,n∈z U z=4π/3+2πn,n∈z не удов усл