divide the first expression by the second.

(12x^3-11x^y-12xy-25y^3)/(3x-5y)

i got lost when divisor has two variables.... thanks

yeah there is an error here.

(12x^3-11x^2y-12xy-25y^3)/(3x-5y)

and it is really 12xy there.

thanks

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- Jan 15th 2009, 08:14 AMprincess_21divide
divide the first expression by the second.

(12x^3-11x^y-12xy-25y^3)/(3x-5y)

i got lost when divisor has two variables.... thanks

yeah there is an error here.

(12x^3-11x^2y-12xy-25y^3)/(3x-5y)

and it is really 12xy there.

thanks - Jan 15th 2009, 08:59 AMjbpellerin
well there are a few ways to do this

first is synthetic division which they tought you in school but I don't quite remember

the next is just simply doing it one step at a time, it comes out to be the synthetic method I believe but this way you can see what you are doing

(12x^3-11x^y-12xy-25y^3)/(3x-5y)

so start with the first term

12x^3, it is 4x^2 times the first term in the bottom

so replace 12x^3 with 4x^2(3x - 5y) + 20yx^2 , is it clear why I did that?

anyways now you have

(4x^2) + (20yx^2-11x^y-12xy-25y^3)/(3x-5y)

and you can keep going

hopefully this helps, I just woke up so I'm still not entirely lucid - Jan 15th 2009, 09:00 AMSoroban
Hello, princess_21!

I will assume there are typos in your problem . . .

Quote:

$\displaystyle (12x^3-11x^{{\color{red}2}}y-12xy^{{\color{red}2}}-25y^3) \div (3x-5y)$

i got lost when divisor has two variables . . . really?

. . $\displaystyle \begin{array}{ccccccc}

& & & 4x^2 & +3xy & +y^2 \\

& & --- & --- & --- & --- \\

3x-5y & ) & 12x^3 & -11x^2y & -12xy^2 & -25y^3 \\

& & 12x^3 & -20x^2y \\

& & --- & --- \\

& & & 9x^2y & -12xy^2 \\

& & & 9x^2y & -15xy^2 \\

& & & -- & --- \\

& & & & 3xy^2 & -25y^3 \\

& & & & 3xy^2 & -5y^3 \\

& & & & --- & --- \end{array}$

. . . . . . . . . . . . . . . . . . . . . . . . . .$\displaystyle -20y^3$

Answer: .$\displaystyle 4x^2 + 3xy + y^2 - \frac{20y^3}{3x-5y} $

- Jan 15th 2009, 09:03 AMIsomorphism
- Jan 16th 2009, 05:51 AMprincess_21
yeah there is an error here.

(12x^3-11x^2y-12xy-25y^3)/(3x-5y)

and it is really 12xy there.

thanks (Wait)