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Homework Help: Natural Log and Exponential

  1. Mar 6, 2010 #1
    1. The problem statement, all variables and given/known data
    Trying to solve for K:

    ln(1-4k)=-6k


    2. Relevant equations



    3. The attempt at a solution
    I know that need to take the e of both side, to get 1-4k=e^-6k, but I cannot remember any properties of e to allow me to remove the k from the exponent. Any tips is appreciated.
     
  2. jcsd
  3. Mar 6, 2010 #2
    Clearly, [tex]k=0[/tex] is a solution.
    to find the another solution you need to use an advanced topic:
    http://mathworld.wolfram.com/LambertW-Function.html
     
  4. Mar 6, 2010 #3
  5. Mar 6, 2010 #4

    vela

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    You have to solve it numerically. You can't solve for k algebraically.

    You can visualize the solutions by plotting the functions y=1-4k and y=e^-6k and seeing where they intersect.
     
  6. Mar 6, 2010 #5
    m/s?? :smile:
     
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