This Demonstration shows how you can numerically compute the inverse of the Laplace transform

of a simple function

:

and

. The selected method is the Fourier series approximation. This method uses the following formula in order to perform the inversion of

:

.
You can select the appropriate values of

and

that give the correct inverse. This choice must be such that

and

, where

is a measure of the maximum relative error and

is the exponential order of

.
The red curve is the sine function and the blue dots are the selected numerical values of the inverse of

.
You can clearly see how this method may fail to give an accurate inverse if the values of

and

are not correctly selected. The first snapshot presents a correct inversion result. The next two snapshots show situations where the method gives erroneous data.