Question

Find the area bounded by the parabola $y=x^2-4,$ the$X$ -axis and the lines$x=-1$ and $x=2$ ?

Answer 1

$Area={\int }_{-1}^{2}0-(x^2-4)={\int }_{-1}^2(4-x^2)dx=4x-\frac{x^3}{3}{\int }_{-1}^2$

$Area=8-\frac{8}{3}-(-4+\frac{1}{4})12-\frac{9}{3}=9$ $sqr$ $units$.