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Homework Help: How to prove this differential expression

  1. Jan 24, 2009 #1
    i need to prove that this expression is correct

    http://img216.imageshack.us/my.php?image=23051510gd6.gif

    f'(x)=d(f(x))/dx
    there is no such structure on the left side of the equation
    there are a defferential in the power of n
    only the d^n


    ??
     
  2. jcsd
  3. Jan 24, 2009 #2

    Mute

    User Avatar
    Homework Helper

    The first thing I would try is the Liebniz product rule:

    [tex]\frac{d^n}{dx^n}(fg) = \sum_{k=0}^n \frac{n!}{k!(n-k)!}f^{(k)}g^{(n-k)}[/tex]

    where [itex]f^{(j)}[/itex] is the jth derivative of f. See if that gets you anywhere.
     
  4. Jan 24, 2009 #3

    Mark44

    Staff: Mentor

    ... or maybe a proof by induction.
     
  5. Jan 24, 2009 #4
  6. Jan 25, 2009 #5
    Last edited by a moderator: May 3, 2017
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