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Algebra question

  1. Apr 21, 2012 #1
    My math skills are failing me, and I was hoping one of you could help me with this real quick..

    I need to solve for i:

    a in this case is based on the interval in the musical scale, so
    [itex]a = 2^{\frac{1}{12}}[/itex]

    I have to solve this in objective c, and apparently it doesn't let me solve logarithms except for bases 2, 10, and e
  2. jcsd
  3. Apr 21, 2012 #2


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    Science Advisor

    Hey rhenretta.

    This kind of problems what is called logarithms. Basically logs and exponentials are inverses in that log(e^x) = x and e(log(x)) = x for valid x's. So we have:

    [itex]log_a(a^{i}) = log_a(b)[/itex] gives us
    [itex]i = log_a(b) = \frac{ln(b)}{ln(a)}[/itex]

    where ln(x) is the natural logarithm function.
  4. Apr 21, 2012 #3
    Thanks chiro :)
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