Question

найдите область определения функции y=sqrt 4cos2 2(x-3)

Answer 1

4cos²2x-3≥0
4*(1+cos4x)/2 ≥3
1+cos4x≥1,5
cos4x≥0,5
-π/6+2πn≤4x≤π/6+2πn
-π/24+πn/4≤π/24+πn/4,n∈z