http://img707.imageshack.us/img707/1045/71577508.jpg

Why is it Ax(x+3) + B(x+3) + Cx^2

instead of Ax^2(x+3) + Bx(x+3) + Cx^3

Printable View

- Dec 9th 2009, 01:07 PMswatpup32I'm having a problem with the following partial fraction
http://img707.imageshack.us/img707/1045/71577508.jpg

Why is it Ax(x+3) + B(x+3) + Cx^2

instead of Ax^2(x+3) + Bx(x+3) + Cx^3 - Dec 9th 2009, 01:11 PMRaoh
- Dec 9th 2009, 01:23 PMswatpup32
I'm sorry, but I still don't understand.

- Dec 9th 2009, 01:25 PMRaoh
- Dec 9th 2009, 01:31 PMswatpup32
okay, I wasn't thinking about it as a fraction. I was only considering the numerator. An, x canceled out from the numerator and denominator.

- Dec 9th 2009, 01:35 PMRaoh
- Dec 9th 2009, 01:40 PMRaoh
$\displaystyle \frac{x^2+8x-3}{x^2(x+3)}$$\displaystyle =\frac{Ax(x+3)+B(x+3)+Cx^2}{x^2(x+3)}$

now get rid of the same denominators and you'll have,

$\displaystyle x^2+8x-3=Ax(x+3)+B(x+3)+Cx^2$