# Partical Fractions

by krnhseya
Tags: fractions, partical
 P: 104 1. The problem statement, all variables and given/known data Turn this into partial fraction. k1b1/[((k1+b1*s)(k2+b2*s))-b1$$^{2}$$s$$^{2}$$] 2. Relevant equations n/a 3. The attempt at a solution original question was to find the transfer function with springs and a damper and I reduced it to this far but I cant get the partial fraction. once i get that partical fractions, i take the inverse laplace transform and get the answer.
 P: 1,757 I'm getting dizzy reading it ... $$\frac{k_1b_1}{(k_1+b_1s)(k_2+b_2s)-b_1^2s^2}$$ Yes?
 P: 104 yeap :)
P: 104

## Partical Fractions

well is this impossible to separate?
i did other problems but i am just stuck on this one.
let me know if you need the actual problem statement...
 PF Patron Sci Advisor Thanks Emeritus P: 38,387 you want, of course, to factor the denominator. I think I would be inclined to multiply out that first part and combine coefficients of like powers. It will be, of course, a quadratic. At worst, you could set the denominator equal to 0 and solve the equation by the quadratic formula.
 PF Patron HW Helper Sci Advisor Thanks P: 25,457 $$\frac{k_1b_1}{(k_1+b_1s)(k_2+b_2s)-b_1^2s^2}$$ krnhseya, just expand the bottom line into the form $$as^2\,+\,bs\,+\,c$$, and then factor it using the good ol' (-b ±√b^2 - 4ac)/2a.
P: 104
 Quote by tiny-tim $$\frac{k_1b_1}{(k_1+b_1s)(k_2+b_2s)-b_1^2s^2}$$ krnhseya, just expand the bottom line into the form $$as^2\,+\,bs\,+\,c$$, and then factor it using the good ol' (-b ±√b^2 - 4ac)/2a.
well that b1 squared and s squared at the end...it cancells the expansion of the squared part...
 PF Patron HW Helper Sci Advisor Thanks P: 25,457 No, it doesn't … It's $$k_1k_2\,+\,(b_1k_2\,+\,b_2k_1)s\,+\,b_1(b_2\,-\,b_1)s^2$$

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