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Homework Help: Log question

  1. Sep 24, 2004 #1
    I'm having a problem with a log question, its rather easy but I'm stuck after certain point.

    The question is:

    10^(x+3)=5e^(7-x)

    I tried solving by:

    ln10^(x+3) = ln5 + lne^(7-x)
    (x+3)ln10 = ln5 + (7-x)

    I am stuck after that, I've tried every combiantion and when I chack it with a calculator answer, my answer is different.

    Any help would be much appreciated, thank you.
     
  2. jcsd
  3. Sep 24, 2004 #2
    (x+3)ln10 = ln5 + 7-x that is correct. Now just put all of the x's to the left hand side and all the rest on the other side : xln10 + x = ln5 + 7 - 3ln10

    x(ln10 + 1) = ln5 + 7 -3ln10

    x = (ln5 + 7 - 3ln10)/(ln10 + 1)

    marlon
     
  4. Sep 24, 2004 #3
    Ah, thank you very much. Your help is much appreciated. I could not fingure out how to get the x's out the correct way. I did not know this was allowed. Thank you again.
     
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