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Homework Help: Integration by parts help?

  1. Aug 30, 2012 #1
    1. The problem statement, all variables and given/known data

    ∫ln(2x+1) Integrate by parts

    2. Relevant equations

    I got xln(2x+1)+[itex]\frac{1}2{}[/itex]ln(2x+1)-x+C

    3. The attempt at a solution

    The solution is [itex]\frac{1}{2}[/itex](2x+1)ln(2x+1)-x+C

    I know the answers are the same,but it's bugging me that I can't simplify the first answer I got to the second answer. Can someone explain it to me?
  2. jcsd
  3. Aug 30, 2012 #2
    Look at the first two terms of your answer. Is there a common factor there that you can pull out?
  4. Aug 30, 2012 #3
    ln(2x+1) But I don't see how that will help?
  5. Aug 30, 2012 #4
    Oh, you can pull the term out, substitute your x from your u substitution, combine some terms, and you get it! Thanks!
  6. Aug 30, 2012 #5
    Glad I could help :)
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