Advanced Math/Logarithms

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Expert: Steve Holleran - 9/14/2008


Question
If log e(x) = -1-log e(y), write down an expression involving x and y which is equal to e^2.

Thank you!

Answer
Hi Selina,

Okay, here's what I see:

      log[e] x = - 1 - log[e] y

      ln x = -1 - ln y       (log[e] = ln)

      ln x + ln y = -1

so     ln (xy) = -1  and that means e^(-1) = xy

      then  e^(-1) = 1/e = xy and then e = 1/(xy)

      so you can write e^2 = 1/(x^2y^2)


Hope this is what you wanted
Steve

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Steve Holleran

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I can help with all math questions from basic math to Calculus. Whether it`s consumer questions, or questions from high school or college students, I have probably dealt with it at some time in my career.

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33 years teaching experience in NJ public schools

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B.S. Mathematics : Wake Forest University 1972 M.S. Mathematics : Monmouth University 1981

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