Подстановка условия
[src]sin(10)^2 - 4*sin(2)^2*cos(a)^2 при a = -4
sin(10)^2 - 4*sin(2)^2*cos(a)^2
$$- 4 \sin^{2}{\left (2 \right )} \cos^{2}{\left (a \right )} + \sin^{2}{\left (10 \right )}$$
sin(10)^2 - 4*sin(2)^2*cos((-4))^2
$$- 4 \sin^{2}{\left (2 \right )} \cos^{2}{\left ((-4) \right )} + \sin^{2}{\left (10 \right )}$$
sin(10)^2 - 4*sin(2)^2*cos(-4)^2
$$- 4 \sin^{2}{\left (2 \right )} \cos^{2}{\left (-4 \right )} + \sin^{2}{\left (10 \right )}$$
sin(10)^2 - 4*cos(4)^2*sin(2)^2
$$- 4 \sin^{2}{\left (2 \right )} \cos^{2}{\left (4 \right )} + \sin^{2}{\left (10 \right )}$$
1 cos(-4 + 2*a) cos(4 + 2*a) cos(20)
- - + ------------- + ------------ - cos(2*a) - ------- + cos(4)
2 2 2 2
$$- \cos{\left (2 a \right )} + \frac{1}{2} \cos{\left (2 a - 4 \right )} + \frac{1}{2} \cos{\left (2 a + 4 \right )} + \cos{\left (4 \right )} - \frac{1}{2} - \frac{1}{2} \cos{\left (20 \right )}$$