Подстановка условия
[src]$$\cos{\left (6 x \right )}$$
$$\cos{\left (6 (3) \right )}$$
$$\cos{\left (3 \cdot 6 \right )}$$
$$\cos{\left (18 \right )}$$
6 6 4 2 2 4
cos (x) - sin (x) - 15*cos (x)*sin (x) + 15*cos (x)*sin (x)
$$- \sin^{6}{\left (x \right )} + 15 \sin^{4}{\left (x \right )} \cos^{2}{\left (x \right )} - 15 \sin^{2}{\left (x \right )} \cos^{4}{\left (x \right )} + \cos^{6}{\left (x \right )}$$