Calculating the Energy of a Function

To calculate the energy of a function, use the following equation.

$ E=\int_{t1}^{t2}{|f(t)|^2dt} $

For clarity, follow the example below.

$ E=\int_{0}^{2\pi}{|2sin(t)|^2dt} $


$ E=2\int_{0}^{2\pi}{|sin(t)|^2dt} $


$ E=\int_0^{2\pi}(1-cos(2t))dt $


$ E=(t-\frac{1}{2}sin(2t))|_{t=0}^{t=2\pi} $


$ E= 2{\pi} $

Calculating the Power of a Function

After you have the energy of a function, calculating the power isn't very difficult. Use the following equation.

$ E=\frac{1}{t_2 - t_1}\int_{t1}^{t2}{|f(x)|^2} $

For our previous example, continue by following below.

$ E=\frac{1}{2{\pi} - 0}\int_{t1}^{t2}{|f(x)|^2} $

$ E=\frac{1}{2{\pi} - 0}*{2\pi} $

$ E= 1 $

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Basic linear algebra uncovers and clarifies very important geometry and algebra.

Dr. Paul Garrett