a) \(\int_{-2}^3 f(x)\ \mathrm{d}x = (3 - (-2))\cdot 5\)
b) \(A_1 = \frac{1}{2}\cdot (1-(-2))\cdot 3\), \(A_2 = \frac{1}{2}\cdot (3-1)\cdot 2\), \(\int_{-2}^3 f(x)\ \mathrm{d}x = A_1 - A_2\).
c) \(A_1 = \frac{1}{2}\cdot (2-(-2))\cdot 2\), \(A_2 = \frac{1}{2}\cdot (3-2)\cdot 1\), \(\int_{-2}^3 f(x)\ \mathrm{d}x = -A_1 + A_2\).