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Integration result varying in mathematica 5.2

  1. Jul 6, 2012 #1
    indefinite integral of Log[x] comes out to be
    -x + x Log[x]

    but, the general solution should be
    x ln(x)+C

    Such things also occur when using DSolve command to solve differential equations.
    Please help!
     
  2. jcsd
  3. Jul 6, 2012 #2
    Why is that the general solution? It's derivative is ln(x)+1, not ln(x).
     
  4. Jul 6, 2012 #3
    Thank you algebrat. I did some copy/paste job from y answers, but its incorrect.......

    The problem I actually had is this:
    My book says Integrate[xˆ2 Log[x],x] will output -(x3/9)+((x3/3)Log(x))

    but I am getting x2 (-x + x Log[x])
    Where have the constants gone???
     
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