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# Heinemann Core 3 Book: Exponential watch

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

lnx + ln(x-3) = 0
2. lnx + ln(x-3) = 0

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