Laplace Transforms
Example x(t)=Step Function
Example Exponential Function
We will now start studying the properties of the Laplace transform. Linearity of Laplace Transforms: If constants . This property can be derived in the following way: then for any
Laplace Transform of a Derivative: If
then
This property can be derived in the following way:
This property shows that the process of differentiation in the time-domain corresponds to multiplication by s in the Laplace domain plus the addition of the constant -x(0). Laplace Transforms of Higher Derivatives: If then
This property can be derived in the following way:
In general we have
Laplace Transform of a Signal Multiplied by an Exponential: If
then
. This property can be derived as follows.
This property shows that multiplication by an exponential in time corresponds to shifting in s. Example: Find the Laplace transform for the following functions
We can find the Laplace transform for t and sin2t using the Laplace transform table. In part (a) we need to shift s by 3 whereas we shift s by -1 in part (b). Therefore the Laplace transforms of the above two functions are given as