Help with differential equation

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SUMMARY

The discussion focuses on solving the homogeneous differential equation given by x(dy/dx) = ye^(x/y) - x. The user attempts to solve the equation using substitution, specifically x = vy, and derives a complex integral that remains unsolved. Despite the user's correct approach, they encounter difficulties with the right side of the equation, which also stumps the software Maple. The consensus is that the steps taken are valid, but further assistance is needed to resolve the integral.

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  • Understanding of homogeneous differential equations
  • Familiarity with substitution methods in differential equations
  • Knowledge of integration techniques, particularly for complex integrals
  • Experience with mathematical software like Maple for solving equations
NEXT STEPS
  • Research methods for solving homogeneous differential equations
  • Learn advanced integration techniques for complex functions
  • Explore the capabilities of Maple for symbolic computation
  • Study substitution methods in detail, particularly the x = vy substitution
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Students studying differential equations, mathematics educators, and anyone seeking to enhance their problem-solving skills in advanced calculus.

Richirude
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Hello :)

I'm trying to solve an homogeneous equation... but it seems that I'm wrong in some step... or something, because I can't complete this problem, look here is what i got:

Homework Statement


Solve the given homogeneous equation:
[tex]x\frac{dy}{dx} = ye^\frac{x}{y} - x[/tex]


2. The attempt at a solution

[tex]x dy = (ye^\frac{x}{y} - x) dx[/tex]

[tex]x dy + ( -ye^\frac{x}{y} + x) dx[/tex]

Using substitution
[tex]x = vy[/tex]

[tex]dx = vdy + ydv[/tex]


[tex]vy dy + (-ye^v + vy) [ vdy + ydv ] = 0[/tex]


[tex](vy + yv^2 - vye^v)dy + (vy^2 - y^2e^v )dv = 0[/tex]


[tex](vy + yv^2 - vye^v)dy = (y^2e^v - vy^2 )dv[/tex]


[tex]\frac{(y)(v + v^2 - ve^v)}{y^2(e^v - v)} dy = dv[/tex]


[tex]\int \frac{1}{y} dy = \int \frac{(e^v - v)}{(v + v^2 - ve^v)} dv[/tex]

The integral on the left side is easy to solve, but I can't find a way to solve the right side of the equation. Maybe I'm wrong in some earlier step...


Any Suggestions?

Thanks and sorry for my English, I'm still learning it (i'm from venezuela)
 
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Your English is quite good; no need to apologize. For what it is worth, I agree with your steps, but I don't see how to work it either. Apparently, neither does Maple.
 

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