Logarithmic Equation with x on both sides

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The discussion revolves around solving the exponential equation 18x^2 = 6e^(2x). Participants clarify the correct interpretation of the equation and the importance of using proper parentheses. It is noted that the equation cannot be solved using elementary functions, but a solution exists that can be found numerically. The intermediate value theorem is suggested as a method to prove the existence of a solution through value testing. Overall, the conversation emphasizes the challenges of solving logarithmic equations with variables on both sides.
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Exponential Equation with x on both sides

Homework Statement



18x^2=6e^(2x)

Homework Equations


I don't know any for the step I got stuck on.


The Attempt at a Solution


3x^2=e^2x
ln3x^2=lne^2x
2ln3x=2x
ln3x=x
 
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Please start using more parentheses, ok? If you mean 3*x^2=e^(2x), then taking logs gives you log(3)+2*log(x)=2*x. The left side is not 2ln3x, whatever that means. You can't solve that using elementary functions. You can prove a solution exists, and you can solve it numerically, but that's about it.
 
Thank you for your reply! And sorry about the lack of parenthesis.

By solving it numerically, do you mean guess and checking values for x? Or actually solving for x?
 
Negima said:
Thank you for your reply! And sorry about the lack of parenthesis.

By solving it numerically, do you mean guess and checking values for x? Or actually solving for x?

Well yes you can guess values using the intermediate value theorem and show that a solution exists.
 
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