cos(2*a)+cos(3*a)+cos(4*a)+cos(5*a) если a=-2 (упростите выражение)

$$cos{left (2 a right )} + cos{left (3 a right )} + cos{left (4 a right )} + cos{left (5 a right )}$$

$$cos{left (2 a right )} + cos{left (3 a right )} + cos{left (4 a right )} + cos{left (5 a right )}$$

cos(2*(-2)) + cos(3*(-2)) + cos(4*(-2)) + cos(5*(-2))

$$cos{left (2 (-2) right )} + cos{left (3 (-2) right )} + cos{left (4 (-2) right )} + cos{left (5 (-2) right )}$$

cos(2*(-2)) + cos(3*(-2)) + cos(4*(-2)) + cos(5*(-2))

$$cos{left (-2 cdot 5 right )} + cos{left (-2 cdot 4 right )} + cos{left (-2 cdot 2 right )} + cos{left (-2 cdot 3 right )}$$

cos(4) + cos(6) + cos(8) + cos(10)

$$cos{left (10 right )} + cos{left (4 right )} + cos{left (8 right )} + cos{left (6 right )}$$

cos(2*a) + cos(3*a) + cos(4*a) + cos(5*a)

2 3 4 5 4 2 3 2 2 2 2 4
cos (a) + cos (a) + cos (a) + cos (a) + sin (a) – sin (a) – 10*cos (a)*sin (a) – 6*cos (a)*sin (a) – 3*sin (a)*cos(a) + 5*sin (a)*cos(a)

$$5 sin^{4}{left (a right )} cos{left (a right )} + sin^{4}{left (a right )} – 10 sin^{2}{left (a right )} cos^{3}{left (a right )} – 6 sin^{2}{left (a right )} cos^{2}{left (a right )} – 3 sin^{2}{left (a right )} cos{left (a right )} – sin^{2}{left (a right )} + cos^{5}{left (a right )} + cos^{4}{left (a right )} + cos^{3}{left (a right )} + cos^{2}{left (a right )}$$