Solving ((y^2)+xy+1)dx+((x^2)+xy+1)dy=0 Using Exact Equations

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SUMMARY

The discussion focuses on solving the differential equation ((y^2)+xy+1)dx+((x^2)+xy+1)dy=0 using the method of exact equations. The user encounters difficulties because the partial derivatives Mx and Ny are not equal, indicating the equation is not exact. The user seeks guidance on how to manipulate the equation to achieve equality between the partial derivatives, specifically looking for a suitable integrating factor. The initial attempt yielded F(xy)=1, which was incorrect as it does not depend on xy.

PREREQUISITES
  • Understanding of exact differential equations
  • Knowledge of partial derivatives
  • Familiarity with integrating factors
  • Basic calculus concepts
NEXT STEPS
  • Research methods for finding integrating factors for non-exact equations
  • Study the application of the formula (N_{x}-M_{y})/(xM-yN)=F(xy)
  • Learn about the conditions for exactness in differential equations
  • Explore examples of solving exact equations in differential calculus
USEFUL FOR

Students studying differential equations, mathematics educators, and anyone seeking to understand the method of exact equations and integrating factors.

TheFirstOrder
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Homework Statement



Solve

((y^2)+xy+1)dx+((x^2)+xy+1)dy=0

using the method of exact equations.

Homework Equations



I must use:

(N[tex]_{x}[/tex]-M[tex]_{y}[/tex])/(xM-yN)=F(xy)

The Attempt at a Solution



The problem that I'm having is that I can't get the required partial derivatives to be equal to each other. How do can I change it so that N[tex]_{x}[/tex]=M[tex]_{y}[/tex]?

When I started this problem initially, I got F(xy)=1, which is not right as 1 is not a function of xy (and I had forgotten to check that the partial derivatives were equal to each other) :P

Please help. It's my first time here.

And sorry, the superscripts are meant to be subscripts!
 
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Since Nx is not equal to My, the equation isn't exact. Are you sure you copied the question correctly?
 
ideasrule said:
Since Nx is not equal to My, the equation isn't exact. Are you sure you copied the question correctly?

Yes, that is the precise equation. And that's how I'm stuck.

Mx=2y+x
Ny=2x+y

I read things in my textbook that says I could times the original equation by a factor that would result in the two partial equations being equal, but that doesn't seem to work in this case. I'm completely clueless.
 

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