# Inverse laplace question help

1. Nov 23, 2006

### cabellos

inverse laplace question help plz....

i am trying find the inverse laplace transfor of s+1/s^2 -4s +4

using partial fractions and solving my answer is e^2t + 3e^2t

however checking this in an online fourier-laplace calculator it comes up with e^2t + 3te^2t

who is correct? could you show me how you get your answer plz....

thanks

2. Nov 23, 2006

### nazzard

Hello cabellos,

I get the same result as your calculator. You might have made a mistake while using the partial fractions method.

$$\frac{s+1}{s^2-4s+4}=\frac{s+1}{(s-2)^2}=\frac{1}{s-2}+\frac{3}{(s-2)^2}$$

Regards,

nazzard

Last edited: Nov 23, 2006
3. Nov 23, 2006

### cabellos

hi, oops im not awake :zzz: ....i used s-2 as the denominator for both A and B. Thanks
:rofl: