SOLUTION: Please simplify x^3 divide by 3x^2-6

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Question 273393: Please simplify x^3 divide by 3x^2-6
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
Actually that is simplified as much as possible.
However, the following is perhaps what you want.

%28x%5E3%29%2F%283x%5E2-6%29

Our goal is to make the numerator as much like the 
denominator as possible.

Factor 3 out of the denominator

%28x%5E3%29%2F%283%28x%5E2-2%29%29

We put the 3 in the bottom to the side as a factor of 1%2F3

1%2F3%22%22%2A%22%22x%5E3%2F%28x%5E2-2%29

Still trying to make that numerator as much like the
denominator as possible

Write x%5E3 as x%28x%5E2%29

1%2F3%22%22%2A%22%22x%28x%5E2%29%2F%28x%5E2-2%29

We put the x in the top to the side along with the
1%2F3 factor making it an x%2F3 factor:

x%2F3%22%22%2A%22%22%28x%5E2%29%2F%28x%5E2-2%29

Still trying to make that numerator as much like the
denominator as possible, we add a -2 and then
a %22%22%2B2 so that the effect will be to add 0:

x%2F3%22%22%2A%22%22%28x%5E2-2%2B2%29%2F%28x%5E2-2%29

Now we will enclose in parentheses the first two terms 
in the numerator which are identical to the denominator

x%2F3%22%22%2A%22%22%28%28x%5E2-2%29%2B2%29%2F%28x%5E2-2%29

Now we make two fractions:

x%2F3%22%22%2A%22%22%28%28x%5E2-2%29%2F%28x%5E2-2%29++%2B2%2F%28x%5E2-2%29%29

The first fraction is 1, so

x%2F3%22%22%2A%22%22%281++%2B2%2F%28x%5E2-2%29%29

Distribute that out and get

x%2F3%2B+%282x%29%2F%283%28x%5E2-2%29%29

That's what you would have gotten if you had done it
by long division.  Did your teacher tell you to
use long division? If so, post again and specify
that we are to do it by long division.

Edwin