Solve 1st Order ODE from Transcendental Equation

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Discussion Overview

The discussion revolves around the approach to solving a transcendental equation of the form y(x)² = 1/(x² log²(A(x) y(x)²)) by transforming it into a first-order ordinary differential equation (ODE). Participants explore the validity of differentiating both sides of the equation to derive y(x).

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant questions whether it is permissible to differentiate the equation y(x)² = 1/(x² log²(A(x) y(x)²)) to obtain a first-order ODE for y(x).
  • Another participant suggests that defining f(x) = y(x)² and solving for f(x) might be a simpler approach, mentioning a logarithmic property to simplify the equation.
  • A different participant challenges the validity of the logarithmic property mentioned, emphasizing concerns about the modifications allowed on differential equations and noting that the resulting differential equation does not depend on A(g), which is a point of annoyance.
  • A later reply acknowledges the mistake regarding the logarithmic property, indicating a casual tone about the oversight.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the appropriateness of the proposed method for solving the equation, and there are competing views on the best approach to take.

Contextual Notes

There are unresolved concerns regarding the modifications allowed in transforming the original equation into a differential equation and the implications of the resulting equation's dependence on A(g).

gonadas91
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It is a general doubt about the following equation: Imagine I want to calculate an unknown function [tex]y(x)[/tex], and my starting equation is of the type

[tex]y(x)^{2}=\frac{1}{x^{2}Log^{2}(A(x)y(x)^{2})}[/tex]

, then, am I allowed to start with the equation

[tex]y(x)=\frac{1}{xLog(A(x)y(x)^{2})}[/tex]

and differenciate in both sides of the equation, to obtain a first order diferential equation to get y(x)?

(Note that the beginning equation is a trascendental equation, but why not trying to solve the first order ODE?)Thank you
 
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I don't see why this wouldn't be allowed but I'd assume setting ##f(x)=y(x)^2## and solving for ##f(x)## would be simpler. You can ofc use ##log(a)^2=log(a)*log(a)=log(2a)## to remove the square on the logarithmic function.
 
Mmm the last property of the logs is not valid. My question actually has to be with the modifications that are allowed on a differential equation. Also, the resulting differential equation using that is not depending on A(g) which annoys me somehow...
 
oh yeah ofc it isn't haha, too late for this here
 

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