Partial fraction decomposition

kristopher0123

New member
Joined
Sep 11, 2009
Messages
19
Hey everyone...umm...yeah I'll just get right to it.

Question:
x^2-x+2
----------
x(x-1)^2

My work:
x^2-x+2
---------- =
x(x-1)^2

A_____B_____ C
--- + -------- + ---
x-1__(x-1)^2__x

I don't know where to go now since x^2-x+2 is unfactorable...or if that even matters. If you can help me, it would be greatly appreciated. Sorry about formatting issues. I don't know how to make it all nice and neat like all of you haha...
 
You don't factor it. Multiply both sides by x(x-1)^2 and multiply it out. Collect like terms, equate coefficients of the powers of x to solve for A,B,C. It will be a linear system.
 
Just an example:

x/(x-2)(x-1) = A/(x-2) + B/(x-1)

Hence

x = A(x-1)+B(x-2)

x = (A+B)x + (-A-2B)

A+B = 1
-A-2B = 0

Solving this gives B=-1 and A=2.
 
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