Energy
$ E_\infty = \frac{1}{t_2-t_1}\int_{t_1}^{t_2}[x(t)]^2 dt $
ex: $ E_\infty = \int_{-\infty}^{\infty} [x(t)]^2 dt $
$ E_\infty = \int_{0}^{3} [1]^2 $
$ E_\infty = 1+1+1+1 = 4 $
Power
$ P_\infty lim N-> - \infty = \frac{1}{2*N+1}\int_{-N}^{N}[x(t)]^2 dt $
$ P_\infty = \frac{1}{2*N+1} * lim N-> -\infty \int_{-N}^{N} [x(N)]^2 $
$ P_\infty = \frac{1}{\infty} * 4 = 0 * 4 = 0 $