# Laplace Transform - (stinking partial fractions)

1. Oct 9, 2005

Ok... I'm working on this laplace transform, and I'm getting stuck on the partial fractions part on this one problem. If someone could help me out with setting it up, I would be very appreciative.

$$\frac{s}{(s^2+4)(s^2+\omega^2 ) }$$

After trying to set it up, I get something like:

$$s=A(s^2+\omega^2)+B(s^2+4)$$

I can't really equate the coefficients with a problem like this. I'm just totally frickn' lost when it comes to this part. My algebra is rather crappy

Last edited: Oct 9, 2005
2. Oct 9, 2005

LaTeX preview not working

When I was typing out this msg, I could not preview any of the LaTeX... but after submitting the thread it displayed as beautiful as it usually does.
Is anyone else having this problem?

Last edited: Oct 9, 2005
3. Oct 9, 2005

### Pyrrhus

$$\frac{s}{(s^2+4)(s^2+\omega^2 ) } = \frac{As + B}{s^2+4} + \frac{Cs + D}{s^2+ \omega^2}$$

4. Oct 9, 2005

### erik-the-red

I think Cyclovenom's answer is correct. For a quadratic factor like $$s^2 + 4$$, you have to $$As + B$$. If it was a linear factor, $$A$$ would suffice.

5. Oct 10, 2005