There is the parabola $x^2.$ what is the area under the curve between 0 and 3?
\(\displaystyle \int_{0}^{3} x^2 dx = 3^2 - 0, \mathrm{which\space is} \ \textcolor{red}{9}\), so the area under the curve from 0 to 3 is 9.
Hi Hipie,
\(\displaystyle \int_{0}^{3} x^2 dx\\~\\ =\left[ \frac{x^3}{3} \right]_0^3=\frac{3^3}{3}-0=9u^2 \)
Yes it is 9.