/
| 3
| 4 cos(2*x) cos (2*x)
| cot (2*x) dx = C + x + ---------- - -----------
| 2*sin(2*x) 3
/ 6*sin (2*x)
$$\int \cot^{4}{\left(2 x \right)}\, dx = C + x + \frac{\cos{\left(2 x \right)}}{2 \sin{\left(2 x \right)}} - \frac{\cos^{3}{\left(2 x \right)}}{6 \sin^{3}{\left(2 x \right)}}$$