C3 - Inversing Logs

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  1. CaligulazBaby's Avatar
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    C3 - Inversing Logs
    ..
    Last edited by CaligulazBaby; 15-08-2012 at 10:24.
  2. Tizoxic's Avatar
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    • Location: Sri Lanka
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    Re: C3 - Inversing Logs
    Remember the addition log law, ie: ln(x) + ln(x-3) =ln(x^2 -3X)
    ..X^2 -3X=1 (Because anything to the power zero is one.) Proceed.
  3. JustAbi's Avatar
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    • Location: London
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    Re: C3 - Inversing Logs
    (Original post by CaligulazBaby)
    Solve the following giving the exact solution.

    "In x + In(x-3) = 0"

    I've tried every method I can think of to solve this over the course of about an hour and still can't get anywhere near the answer in the answerbook.
    You can combine them and say:
    ln x(x-3)=0
    ln x^2-3x=0
    x^2-3x=1 (as e^0 is 1)
    x^2-3x-1=0

    Edit: basically the same as the guy above
  4. CaligulazBaby's Avatar
    • Respected Member
    • Location: Candyland
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    Re: C3 - Inversing Logs
    ..
    Last edited by CaligulazBaby; 15-08-2012 at 10:24.
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