Question

Решите неравенство
$4cos^{2} 2x geq 3$

Answer 1

2(1+cos4x)≥3
2cos4x≥1
cos4x≥1/2
-π/3+2πn≤4x≤π/3+2πn,n∈z
x∈[-π/12+πn/2;π/12+πn/2,n∈z}