1 вариант
S = int (-1 0) (x + 1) dx + int (0 pi/2) cos x dx =
= (1/2 * x^2 + x)_{-1}^{0} + (sin x)_{0}^{pi/2} =
= ((1/2 * 0^2 + 0) - (1/2 * (-1)^2 + (-1)) + sin pi/2 - sin 0 =
= -1/2 + 1 + 1 = 3/2.
Ответ: S = 3/2.