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Solving an equation

  1. Jul 29, 2009 #1
    1. The problem statement, all variables and given/known data
    To solve the following equation for x in terms of R and 3 constants a,b, and c:

    R = ((a^-x)-(b^-x))/((c^-x)-(a^-x))

    2. Relevant equations

    Just the given equation

    3. The attempt at a solution

    I have tried taking the natural log of both sides but that doesn't seem to get me anywhere. Any suggestions?
  2. jcsd
  3. Jul 29, 2009 #2


    Staff: Mentor

    Your equation can be rewritten as
    [tex]R = \frac{1/a^x - 1/b^x}{1/c^x - 1/a^x}[/tex]

    I would start with combining the two expressions in the numerator and the two in the denominator and simplify, then see where that takes me.
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