Решите уравнение [tex] cos^{2} \frac{x}{3} + sin ^{4} \frac{x}{3} = 1[/tex]

(1+cos(2x/3))/2+(1-cos(2x/3))²/4=12+2cos(2x/3)+1-2cos(2x/3)+cos²(2x/3)=4cos²(2x/3)=1(1+cos(4x/3))/2=11+cos(4x/3)=2cos(4x/3)=14x/3=2πnx=3πn/2,n∈z