Question:

Sum of algebraic area = $\frac{-1}{2} + 2 = \frac{3}{2}$.<br>Alternatively, using the Fundamental Theorem of Calculus: on $[a, b]$, then $\int_{a}^{b} f(x) dx = F(b) - F(a)$ where $F$ is any antiderivative of $f$, that is, a function such that $F' = f$.