Categorize first order differential equation

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Homework Help Overview

The discussion revolves around categorizing first order differential equations, specifically focusing on the equation dy/dx = -y²/(x² + 4xy). Participants are exploring various categories such as linear equations, homogeneous equations, Bernoulli equations, exact equations, and separable equations.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to categorize the given differential equation but struggles to transform it into a recognizable form. They express uncertainty about their approach and seek guidance on whether they are missing something obvious.

Discussion Status

Some participants have pointed out that the equation may fit the category of homogeneous equations of degree 2, which has led to a realization for the original poster. There appears to be a productive direction emerging from the discussion.

Contextual Notes

The original poster expresses a desire to categorize the equation for easier solving, indicating a focus on understanding the classification of differential equations. They also mention the possibility of sharing additional work if needed.

BlueSocks
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Homework Statement


I'm trying to determine which categories various first order differential equations fall into (and once they're categorized they're nice and easy to solve). My list of categories is the following; linear equations, homogenous equations, bernoulli equations, exact equations, exact equations with special integrating factors, separable equations, equations with linear coefficients, and equations that fit the form y'=g(ax+by).

However, I can't seem to transform the following equation into anything that would fit any of the above.

dy/dx=-y2/(x2 + 4xy)


The Attempt at a Solution



I've tried transforming the equation in pretty much every way I can think of, but I'm not finding any readily solvable form. the closest I've gotten (I think) is y' =(x2/y2 - 4x(1/y))-1 but other than isolating y' (in a different way), that doesn't seem to be much good. Am I missing something obvious here? Sorry, I feel a little silly. If that's not enough attempt at a solution I can show my work for all the other forms of the equation that I've worked to.

Thank you very much for any direction/assistance you might provide.


Cheers!
 
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BlueSocks said:

Homework Statement


I'm trying to determine which categories various first order differential equations fall into (and once they're categorized they're nice and easy to solve). My list of categories is the following; linear equations, homogenous equations, bernoulli equations, exact equations, exact equations with special integrating factors, separable equations, equations with linear coefficients, and equations that fit the form y'=g(ax+by).

However, I can't seem to transform the following equation into anything that would fit any of the above.

dy/dx=-y2/(x2 + 4xy)

Doesn't that fit your category M and N are homogeneous of degree 2?
 
...yup. Well, I feel incredibly silly all of a sudden. Thank you, I really appreciate you pointing that out. I think I'll be good from here on in.
 
Indeed, the ODE can be written in the form [tex]\frac{dy}{dx}=f\left(\frac{y}{x}\right)[/tex]
 

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