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Heinemann Core 3 Book: Exponential watch

    • Thread Starter

    im kinda stuck with what to do...help appreciated

    lnx + ln(x-3) = 0

    lnx + ln(x-3) = 0

    ln(x(x-3)) = 0
    x(x-3) = 1
    x² - 3x - 1 = 0

    (Original post by yazan_l)
    lnx + ln(x-3) = 0

    ln(x(x-3)) = 0
    x(x-3) = 1
    x² - 3x - 1 = 0
    I'd go a little further because if you solve for the roots you get

    x = [3+rt(13)]/2 or [3-rt(13)]/2

    and putting the latter of those (which is negative) back into the original question doesn't make a lot of sense.
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Updated: May 10, 2005

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