Question

Решите уравнение cos4x cos2x+sin4x sin2x =0

Answer 1

$cos4x, cos2x+sin4x, sin2x=0\\cos(4x-2x)=0\\cos2x=0\\2x=frac{pi}{2}+pi n; ,; nin Z\\x=frac{pi}{4}+frac{pi n}{2}; ,; nin Z$