# Long Division of Polynomials

• Nov 30th 2011, 09:53 AM
annon25
Long Division of Polynomials
Hey Everyone,
Thanks for your help with substitution yesterday. I have a question regarding long division of polynomials, and I was hoping someone would be able to help me figure out why I'm getting stuck.

Here is the problem:

4y^3-5y/2y-1

These are my steps so far:

4y^3/2y=2y^2

2y^2(2y-1)

4y^3-5y-4y^2+2y^2 = y- 3y^2

That's as far as I got; and I'm pretty sure it's a careless mistake somewhere, but I'm doing this like the rest of the problems that I've been getting correctly.

Thanks again for your help. Big test in 8 hours!

Happy Wednesday, everyone.
• Nov 30th 2011, 10:41 AM
Soroban
Re: Long Division of Polynomials
Hello, annon25!

Have you been taught the standard long division format?

Quote:

$\displaystyle (4y^3-5y) \div (2y-1)$

$\displaystyle \begin{array}{cccccccccc} &&&& 2y^2 & + & y & + & 3 \\ && --&--&--&--&--&--&-- \\ 2y-1 & | & 4y^3 &.&.& + & 5y&.&. \\ && 4y^3 & - & 2y^2 \\ && -- & -- & -- \\ &&&& 2y^2 & + & 5y \\ &&&& 2y^2 & - & y \\ &&&& -- & -- & -- \\ &&&&&& 6y \\ &&&&&& 6y & - & 3 \\ &&&&&& -- & -- & -- \\ &&&&&&&& 3 \end{array}$