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Math Help - Finding the Inverse of a Logarithmic Function

  1. #1
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    Finding the Inverse of a Logarithmic Function

    Hey Guys, I am looking to send in my homework by tomorrow morning and was hoping someone would help me with this question.

    What is the equation of the inverse function of the following:

    y = -log(base 5) (-x)


    Thanks for any help you guys or girls can provide!

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  2. #2
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    Quote Originally Posted by lil_cookie View Post
    y = -log(base 5) (-x)
    Why is this harder than the other 100 you have done successfully?

    1) Think it through.

    Domain x < 0. Do you see why?

    2) Swap and Solve

    x = -log_{5}(-y)

    -x = log_{5}(-y)

    5^{-x} = -y

    -\left(5^{-x}\right) = y

    3) Well, that's the algebra. Does it work? Is it a function? Does it need restrictions? Why did I worry about the original Domain?
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  3. #3
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    I'm always nervous when I post four questions and get no response. I DO hope you get it.
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  4. #4
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    Oops, I thought I replied you but I must have forgotten.

    Yes I did get it, your help is verrry much appreciated
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