# HELP! Inverse Laplace Transform

1. Apr 9, 2009

### Patton84

I'm having some trouble getting the inverse Laplace to the following problems...I need some help

F(s)=24/s^5

F(s)= 4/[((s-2)^2)+25

F(s)= s/(s-1)(s+1)

2. Apr 10, 2009

### rock.freak667

For the first one, consider L{tn} works out to be for n>0.

For the second one what is

$$L^{-1} (\frac{1}{s^2+k^2)$$

for the third one, split into partial fractions.

3. Apr 10, 2009

### Patton84

would this be right for the third one

A/s-1 + B/s+1 = s

4. Apr 10, 2009

### djeitnstine

Yes that's correct.

5. Apr 10, 2009

### coomast

No that is wrong, the right formula is:

$$\frac{s}{(s-1)(s+1)}=\frac{A}{s-1}+\frac{B}{s+1}$$

from which you need to determine A and B.

coomast

6. Apr 10, 2009

### djeitnstine

Oops I thought he multiplied it out and set it equal to s