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Homework Help: Quick e Question

  1. Aug 6, 2010 #1
    What does e^(xln(y)) equal?

    EDIT: x being a number, -1.18
     
    Last edited: Aug 6, 2010
  2. jcsd
  3. Aug 6, 2010 #2
    e^(xln(y)) = (e^ln(y))^x = y^x

    *@hgfalling corrected :)
     
    Last edited: Aug 6, 2010
  4. Aug 6, 2010 #3
    Wait, what?

    [tex] e^{x \ln y} = (e^{\ln y})^x = y^x [/tex]
     
  5. Aug 6, 2010 #4
    ok, thankyou but it actually didn't help, my problem is below:

    maCln(t/600)+mbCvln(t/500)=0

    Where ma, C, mb and Cv are known, how do I work out t?
     
  6. Aug 6, 2010 #5

    Char. Limit

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    Gold Member

    Make both sides a power of e. But first, turn it into one logarithm.

    [tex]a log(x) + b log(y) = log(x^a y^b)[/tex]
     
  7. Aug 7, 2010 #6
    Doing that gives me:

    (t/600)^(26x10^3)x(t/500)^(21.99x10^3)=0

    Which doesn't seem solvable to me!

    Any ideas?
     
  8. Aug 7, 2010 #7

    Dick

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    Science Advisor
    Homework Helper

    Try another log rule. Like ln(t/600)=ln(t)-ln(600).
     
  9. Aug 7, 2010 #8
    Thanks for all the help, think I've got it sorted now!
     
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