ENERGY
The energy of a signal can by computed by the following Energy formula:
$ E = \int_{t_1}^{t_2} y(t)\, dt $
on the other hand, power of a signal can be calculated by:
$ P = \frac{1}{t_2 - t_1} \int_{t_1}^{t_2} y(t)\, dt $
Let's now calculate the energy and power of the following signal: $ y(t) = x^{2} $ for $ t_1 = 0 $ and $ t_2 = 5 $
$ E = \int_{0}^{5} x^{2}\, dt = \frac{1}{3} \left [ x^{3} \right ] _0^5 = \frac{125}{3} $
$ P = \frac{1}{5 - 0} \int_{0}^{5} x^{2}\, dt = \frac{25}{3} $
