MHB Natural logs solve ln⁡((x-1)/(x-3))=2

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The discussion revolves around solving the equation ln((x-1)/(x-3))=2. The user initially derives x = 2/(e^2-1) but is confused by the lecturer's solution of x = (3e^2-1)/(e^2-1). A key step involves multiplying both sides of the equation by (x-3) to rearrange it into the form x(e^2 - 1) = 3e^2 - 1. The correct manipulation leads to the lecturer's solution, which approximates to 3.313035285. The thread concludes with a reminder to continue discussions in a linked thread to avoid duplicates.
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hi , hope someone can help as i can't get past a certain step
the natural logs is the problem
ln⁡((x-1)/(x-3))=2
i can get to this point here -1 = e_x^2-x-3
-1+3=x(ⅇ^2-1)
2 = x(ⅇ^2-1)
2/((ⅇ^2-1) )=x((ⅇ^2-1)/(ⅇ^2-1))
X = 2/(ⅇ^2-1)
the solution i got was this x= (2/(ⅇ^2-1)) → 0.3130352855

but the lecturer gave a solution of
(3ⅇ^2-1)/(ⅇ^2-1) = 3.313035285 how do i get to this
 
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blackfriars said:
hi , hope someone can help as i can't get past a certain step
the natural logs is the problem
ln⁡((x-1)/(x-3))=2
i can get to this point here -1 = e_x^2-x-3
-1+3=x(ⅇ^2-1)
2 = x(ⅇ^2-1)
2/((ⅇ^2-1) )=x((ⅇ^2-1)/(ⅇ^2-1))
X = 2/(ⅇ^2-1)
the solution i got was this x= (2/(ⅇ^2-1)) → 0.3130352855

but the lecturer gave a solution of
(3ⅇ^2-1)/(ⅇ^2-1) = 3.313035285 how do i get to this
If $\ln\left(\frac{x-1}{x-3}\right) = 2$ then $\frac{x-1}{x-3} = e^2.$ Multiply both sides by $x-3$ to get $x-1 = (x-3)e^2.$ Then rearrange that as $x(e^2 - 1) = 3e^2 - 1$. That gives $x = \dfrac{3e^2-1}{e^2-1} \approx 3.313035...$.
 
hi sorry for the questions but i cannot transpose the formula to make x the subject could you show the workings for making x the subject
thanks
 
Same topic and a working found http://mathhelpboards.com/pre-algebra-algebra-2/logs-22167-new.html. Thread closed - please continue discussion in linked thread.

blackfriars, please do not post duplicate topics; thanks. :D
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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