Signal Energy
Signal Energy expended from $ t_1\! $ to $ t_2\! $ for CT functions is given by the formula $ E = \int_{t_1}^{t_2} \! |x(t)|^2\ dt $
The total signal energy for a signal can be found by taking the limits for the integral $ t_1\! $ and $ t_2\! $ as $ -inf\! $ and $ inf\! $ respectively