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Homework Help: Solving equation with log

  1. Feb 5, 2012 #1
    1. The problem statement, all variables and given/known data
    Can you solve an unknown equal to some constant+log of unknown.
    please see attached.
    All the other variables are known, except Ic1.
    How to you solve this?

    2. Relevant equations

    3. The attempt at a solution
    I have no idea.

    Attached Files:

    • eqn.png
      File size:
      3.4 KB
  2. jcsd
  3. Feb 5, 2012 #2


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    Science Advisor

    If you have [itex]I_{C1}[/itex] both "inside" and "outside" the logarithm, the equation cannot be solved in terms of "elementary" functions. It very likely can be solved, though still non-trivial, in terms of the "Lambert W function" which is defined as the inverse function to [itex]f(x)= xe^x[/itex].
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