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Homework Help: Check my Integration

  1. Mar 28, 2012 #1


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    Gold Member

    1. The problem statement, all variables and given/known data

    http://i.minus.com/j5qAhbyrxc1jX.jpg [Broken]

    2. Relevant equations

    ∫1/x dx = ln(x)

    3. The attempt at a solution

    Can you guys check my work? I got the solution above and I've been pounding my head against the wall for the last two hours as to why that solution, according to my book, is incorrect.

    The solution, according to the book, is

    (1/3)ln(ln(x)) + c
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Mar 28, 2012 #2


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    Homework Helper

    If you use that ln(x^3)=3*ln(x) you can show that your answer is the same as the books, with an extra additive constant.
  4. Mar 28, 2012 #3


    Staff: Mentor

    Both answers are correct. If you differentiate both answers, you wind up with the integrand.

    Tip: Your work would have been simpler if you had written ln(x3) as 3ln(x).
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