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Math Help - Inverse of this function...

  1. #1
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    Inverse of this function...

    y=2e^(-x)

    Is it
    y=ln(2/x) ?
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  2. #2
    Super Member 11rdc11's Avatar
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    y = -\ln\bigg(\frac{x}{2}\bigg)
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  3. #3
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    Are they the same?

    If x=2,
    y=2e^(-2)=0.2706

    So for the inverse, if x=0.2706
    y=-ln(0.2706/2)=2
    and
    y=ln(2/0.2706)=2

    Am I correct in saying that the two functions (y=-ln(x/2) and y=ln(2/x)) are the same?
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  4. #4
    Super Member 11rdc11's Avatar
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    Yep its the same
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  5. #5
    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by MegaVortex7 View Post
    Am I correct in saying that the two functions (y=-ln(x/2) and y=ln(2/x)) are the same?
    i just want to clarify 11rdc11's response

    recall: \log_a (x^n) = n \log_a x

    so - \ln \bigg( \frac x2 \bigg) = \ln \bigg( \frac x2 \bigg)^{-1} = \ln \bigg( \frac 2x \bigg)
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