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Quick question about exponential and logarithms

  1. May 8, 2013 #1
    If I have ln(e^(-8.336/10c)) wouldn't that be the same as ln(e^(1/(8.336/10c))) therefore = 1/(8.336/10c) = 10c/8.336? I am confused about this because in my lecture notes they simplified ln(e^(-8.336/10c)) to just = -8.336/10c :confused:

    Your help would be appreciated!
  2. jcsd
  3. May 8, 2013 #2


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    Hey rlm42 and welcome to the foums.

    If you let x = -8.336/10c and use the fact that e^(ln(x)) = ln(e^(x)) = x then it means that

    ln(e^(x)) = x = ln(e^(-8.336/10c)) = -8.336/10c.

    All I'm doing is replacing a complex variable with a simple variable and using the identities for logarithms and exponentials.
  4. May 8, 2013 #3
    nvm thnaks!
    Last edited: May 8, 2013
  5. May 9, 2013 #4


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    e^(-a) = 1/(e^a) not e^(1/a). There is a difference.
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