# Laplace splitting fraction

1. Jan 9, 2008

### reece

Basically I don't know how F(s) can be split up to below.

F(s) = $$\frac{1}{s^{2}(s-2)}$$

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

I thought it would be 1/s^2 - 1 / s-2

How does this work? Please explain.
thanks

2. Jan 9, 2008

### rezwan

hey

try using partial fraction:

1/s^2(s-2)=A/s+B/s^2+C/(s-2)
then multiply both side of the identity by s^2(s-2)
then group the terms: s^2,s and constants(terms without s)
finally equate both sides of the identity. and then calculate A,B C
and then put in the term A/s+B/s^2+C/(s-2)
then you will find the expected form.

thanks

rezwan