Solving Non-linear First Order ODEs with Variable Coefficients?

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Homework Help Overview

The problem involves solving a nonlinear first-order ordinary differential equation (ODE) with variable coefficients, specifically the equation $$y' y + \frac{y}{x} = 1 - 2x$$. The original poster indicates that this is not a homework problem but rather a personal challenge.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts a quadratic solution but finds it unsuccessful. They seek further ideas. Some participants question the notation used for the function y, clarifying that y represents y(x). Others mention the equation's classification as a special case of an Abel differential equation and share a link for potential guidance. There is discussion about the effectiveness of substitutions and whether the problem has been analytically solved.

Discussion Status

The discussion is ongoing, with participants exploring various interpretations and approaches. Some guidance has been offered regarding the classification of the equation and potential substitutions, but no consensus has been reached on a viable solution or method.

Contextual Notes

Participants note the complexity of nonlinear equations and express uncertainty about the existence of an analytical solution for the problem presented.

member 428835

Homework Statement


$$y' y + \frac{y}{x} = 1 - 2x$$

Homework Equations


nothing comes to mind

The Attempt at a Solution


i've guessed a quadratic but that didn't work. now I'm stuck. any ideas? also, this is not homework, but a problem I am working on.

Thanks!
 
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Is y y(x)?
 
sorry, yes, ##y = y(x)##
 
LCKurtz said:
Nonlinear equations can seem deceptively simple. This is a special case of an Abel DE of the second kind. This link may or may not be helpful:
http://eqworld.ipmnet.ru/en/solutions/ode/ode0125.pdf
This is an interesting website. When I perform their substitutions I arrive at $$y \frac{dy}{dz} -y = \frac{2x - 1}{\ln | x |} : z:= \int -\frac{1}{x} dx$$ but from here their table provides no further help. Do you suppose this problem has never been analytically solved?
 
joshmccraney said:
This is an interesting website. When I perform their substitutions I arrive at $$y \frac{dy}{dz} -y = \frac{2x - 1}{\ln | x |} : z:= \int -\frac{1}{x} dx$$ but from here their table provides no further help. Do you suppose this problem has never been analytically solved?

I have no idea but it wouldn't surprise me.
 
This did appear deceptively easy at first glance =/
 

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