Решите,уравнение sin^4x/2-cos^4x/2=1/2nd

Question

Решите,уравнение sin^4x/2-cos^4x/2=1/2nd

Answer 1

sin^4x/2-cos^4x/2=1/2

(sin^2x/2-cos^2x/2)*(sin^2x/2+cos^2x/2)=1/2

sin^2x/2-cos^2x/2 = 1/2 

cos x = - 1/2

x=пи-пи/3+2пи*n

х=±2пи/3+2пи*n