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Homework Help: Algebra Question(Part of a Larger Problem)

  1. Feb 12, 2008 #1
    1. The problem statement, all variables and given/known data
    f(x) = (2x)(x-5)^(3) + 3x^2(x-5)^(2)

    Need to simplify.


    2. Relevant equations



    3. The attempt at a solution
    I tried simplifying completely but my answer wasn't even close. The Back of the book has:
    5x(x-5)^(2)(x-2)

    I know its easy, but I'm drawing a blank...can anyone start me off on the right path to find how they got that answer?
     
  2. jcsd
  3. Feb 12, 2008 #2

    Dick

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    The first thing to notice is that both terms in your expression have a common factor of x*(x-5)^2. Factor that out. Now what's left in each term?
     
  4. Feb 12, 2008 #3
    Well, wouldn't it then be 2(x-5) + (3x+1)?
     
  5. Feb 12, 2008 #4

    Dick

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    I get just 2(x-5)+3x. Where did the 1 come from?
     
  6. Feb 12, 2008 #5
    Oh! I got it!

    Oh wow. I can't believe I had made a mistake like that. Thank you so much. I just figured it out.

    Thanks Dick.
     
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