Cos 2x cos x – sin 2x sin x =0

Question

Cos 2x cos x – sin 2x sin x =0

Answer 1

cos 2x cos x – sin 2x sin x =0

cos(2x+x)=0

cos3x=0

3x=П/2+Пn

x=П/6+Пn/3

Ответ:П/6+Пn/3