2 вариант
S = int (-pi/2 -1) cos x dx + int (-1 0) (cos x - (x + 1)) dx =
= (sin x)_{-pi/2}^{-1} + int (-1 0) (cos x - x - 1) dx =
= sin (-1) - sin (-pi/2) + (sin x - 1/2 * x^2 - x)_{-1}^{0} =
= -sin 1 + 1 + ((sin 0 - 1/2 * 0 - 0) - (sin (-1) - 1/2 * (-1)^2 - (-1))) =
= -sin 1 + 1 + sin 1 + 1/2 - 1 = 1/2.
Ответ: S = 1/2.