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# C3 - Inversing Logs Tweet

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1. C3 - Inversing Logs
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Last edited by CaligulazBaby; 15-08-2012 at 10:24.
2. 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. 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. Re: C3 - Inversing Logs
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Last edited by CaligulazBaby; 15-08-2012 at 10:24.