Can a Taylor series approximation be used to solve a mixed logarithmic equation?

AI Thread Summary
The discussion focuses on solving the mixed logarithmic equation e^(-66/x)/x^2 = c, where c is a constant. The user attempts to simplify the equation by taking the natural logarithm and rearranging it, leading to -33/x - ln(x) = c/2. They explore using a Taylor series approximation for ln(x) to find an approximate solution but express uncertainty about its effectiveness. It is noted that the equation cannot be solved using elementary functions, indicating a need for approximation methods. The conversation emphasizes the challenges of finding precise solutions for such equations.
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"mixed" logarithmic equation

Homework Statement


I'm trying to solve for x in the following equation: e^(-66/x)/x^2 = c, where c is a constant

Homework Equations


The Attempt at a Solution


By taking ln of both sides and then dividing by 2, I get to:

-33/x -ln(x) = c/2

Then, in order to get an approximate answer, I tried substituting e with its approximation up to a few decimal places, in the original problem statement, but that didn't get me far. I'm considering doing a Taylor series approximation for the 'ln(x)' term (i.e (x-1) - (x-1)^2 + (x-1)^3)) and then solving for x. Is there an easier and/or more precise and/or more direct way? Note, I understand that the taylor approximation I used is meant for x, such that |x| is at most 1. This is why I only went with 3 terms.

Homework Statement


Homework Equations


The Attempt at a Solution

 
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Have you considered arranging it in such a way where the X could be factored out?
 


Considered? Yes. But can't think of how.
 


The equation can't be solved in terms of elementary functions - in other words, you can't factor out an x - so you will need to find an approximate solution to the problem.
 
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