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Homework Help: Partial Differentiation

  1. Sep 3, 2008 #1
    Do you guys know if it's possible to solve for the following integral

    l(t)=∫ {a+ [b+cL(t)+exp^L(t)]/d } dt

    where a, b, c and d are constants and the derivative of L(t) is l(t).

    Thanks in advance!!!
  2. jcsd
  3. Sep 3, 2008 #2


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    Homework Helper

    If you differentiate both sides, you get a DE of the form:
    L'' = f(L).

    You have by the chain rule:
    d^2 L /dt = (dL/dt) d/dL (dL/dt) and
    L'' = L' d/dL (L') = d/dL 1/2 (L')^2 = f(L) which is separable.

    EDIT: Why does your thread read "partial differentiation"?
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