Parital fractions?

1. Nov 7, 2006

pivoxa15

I have never remebered the different partial fraction forumlas. Is there a way to decide which partial fraction formula to use just by looking at the expression?

2. Nov 7, 2006

Office_Shredder

Staff Emeritus
Partial fraction formulae?

I thought you just did partial fractions... what's the context? Normally you just split the fraction after factoring the denominator into a sum of fractions with denominators equal to the different factored parts

3. Nov 7, 2006

mathwonk

over R, the only prime polynomials are linear or quadratic. the numerators are either constant or linear respectively.

if f^n is a factor of the denominator, where f is prime, we need to allow for all fractions whose greatest common denom is f^r, so we have

to allow a/f , b/f^2, c/f^3, ...., d/f^n, for appropriate numerators.

e.g. to decom,pose h/[x^2(x^2+x+1)^3] we set it equal to

a/x + b/x^2 + (cx+d)/(x^2+x+1) +(ex+f)/(x^2+x+1)^2 + (gx+h)/(x^2+x+1)^3.

where a,b,c,d,e,f,g,h, are constants.

Last edited: Nov 7, 2006
4. Nov 8, 2006

pivoxa15

Is that all there is to partial fractions? It isn't as mystifying as it appears.

5. Nov 8, 2006

arildno

Yes it is!
No, it isn't!