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Tryimg to understand this logarithmic identity

  1. Aug 11, 2013 #1
    (I know the title contains a typo, but I can't edit it!)

    I'm trying to understand and/or prove this identity:

    blogbx = x

    I've inserted numbers, and it does work, but I just don't seem to understand why. I mean, some identities are obvious, like:

    logb bx = x

    since bx = bx

    but I can't make any sense of the top one.

    Also, I'm sorry for posting a lot. This is my third thread today!
     
    Last edited: Aug 11, 2013
  2. jcsd
  3. Aug 11, 2013 #2

    micromass

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    The logarithm of ##x## is the unique number ##n## such that ##b^n =x##, right? So ##n=\log_b(x)##. Thus ##b^{\log_b(x)}=b^n = x##.
     
  4. Aug 11, 2013 #3
    Well, now that you wrote it micromass, I guess it seems kind of simple. I'm going to print this one out so I can study it some more!
     
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