# Understanding the concept of laplace transformations

1. Apr 26, 2005

### slug

I'm having trouble understanding the concept of laplace transformations.

my book states that it is comparing how much a function y(t) is like a standard function. what exactly does the answer mean such as y(s)=1/(s-2)
is this the differnence between the functions depending on the value of s

and further more how does taking the integral from zero to infinity of two functions tell me how much alike they are

stupid vague books i hate when they pull equations out of the air and don't explain where they come from and what they mean

2. Apr 26, 2005

### Corneo

The idea of Laplace Transformations is to transform a function in terms of t into s. Do some algebraic work and then take the inverse Laplace transform for the solution.

So given that you have a function in terms of s, that needs to be inversed transformed. You like it up in a table to see that your $Y(s) = \frac {1}{s-2}$ is in the form

$$F(s) = \frac {1}{s-a}$$ and its inverse transform is

$$\mathcal{L}^{-1} \{F(s)\} = e^{at}$$

So for you

$$\mathcal{L}^{-1} \{F(s)\} = e^{2t}$$