1. partial fraction

i'm having trouble to find A, B, C, D:
$\frac{6}{[(s+1)^2 + 1]^2} = \frac{As + B}{(s+1)^2 + 1} + \frac{Cs + D}{[(s+1)^2 + 1]^2}$
Thanks

2. Re: partial fraction

The second term has degree 4, so you should have a degree 3 expression in the numerator... Cx^3 + Dx^2 + Ex + F

3. Re: partial fraction

you are right hurz, but it will be easier to write denominator as s^2 + 2s + 2