Logarithm with Different Base: Solving for x/y

  • Thread starter Thread starter songoku
  • Start date Start date
  • Tags Tags
    Base Logarithm
AI Thread Summary
The problem involves solving the equation 2*log_2(x-2y) = log_3(xy) to find the ratio x/y. The initial steps include transforming the logarithmic expressions and attempting to equate them through change of base. However, a participant points out that log_2(3) is not an integer, suggesting that the equation cannot yield a solution for x/y. The discussion concludes with an acknowledgment that the problem may indeed be unsolvable as posed.
songoku
Messages
2,467
Reaction score
382

Homework Statement


Hi everyone

I need help for this problem :

If 2*\log_2 (x-2y)=\log_3 (xy) , find \frac{x}{y}


Homework Equations


\log_bx = \frac{\log_ax}{\log_ab}


The Attempt at a Solution


2*\log_2 (x-2y)=\log_3 (xy)

\log_2 (x-2y)^2=\log_3 (xy)

\frac{\log_2 (x-2y)^2}{\log_2 2}=\frac{\log_2 (xy)}{\log_2 3}

\log_2 (x-2y)^2 * \log_2 3 = \log_2 (xy)

Then, I stuck ...

Thx :)
 
Physics news on Phys.org
Are you sure you wrote the question down correctly? I ask because log23 is not an integer and you be basically computing (x-2y)k=xy where k is not an integer (so you'd not be able to find x/y)
 
Hi rock.freak667

At least that's the whole question that was given to me by my friend. Your post assure me that this question can't be solved.

Thx a lot for pointing out that \log_2 3 is not an integer :smile:
 
Back
Top