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Math Help - [SOLVED] simple natural log with function e

  1. #1
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    [SOLVED] simple natural log with function e

    Hi,
    can someone explain why: 2e^{-ln(2)}=1
    I understand what the answer would be if the negative wasn't there.
    Thanks,
    Matt
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  2. #2
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    1) a^{-x} = \frac{1}{a^x}
    2) e^{ln(x)} = x

    Or also, a \cdot ln(x) = ln(x^a)
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  3. #3
    MHF Contributor chisigma's Avatar
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    Two basic properties of the exponential function and its inverse...

    \forall a > 0 ,  e^{\ln a} = a (1)

    \forall b,  e^{-b} = \frac{1}{e^{b}} (2)

    Kind regards

    \chi \sigma
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  4. #4
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    haha wow, I can't believe I forgot something that simple in regards to the negative power. Thanks for the help guys!
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