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Multiplying Rational Expressions

  1. Apr 2, 2006 #1
    This is a question I have to do for tomorrow


    I just factor the tops and then cancel where I can. This is what I came up with:


    But the answer key says:


    What have I done wrong?
  2. jcsd
  3. Apr 2, 2006 #2
    You aren't factoring carefully enough. You've got leftover factors floating around. Write out ALL of the steps!


    [tex]=\frac{(2x+1)(2x+1)}{x} \times \frac{3x^4}{3(2x-1)(2x+1)}[/tex]

    NOW do your cancelling.

  4. Apr 2, 2006 #3
    Ouch. That hurt my pride. I forget to factor the factor usually, that's going to kill me one day.

    thanks for pointing out that pesky little mistake.
  5. Apr 3, 2006 #4
    Happens to the best of us. No worries, mate! :biggrin:

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