- #1
fluidistic
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Homework Statement
I must solve [itex]x^2y'+y^2=xyy'[/itex].
Homework Equations
Not sure but I think that [itex]f(tx,ty)=t^nf(x,y)[/itex] could help.
The Attempt at a Solution
My first reflex was to define a new variable [itex]z=y^2[/itex] but I was stuck a few steps further.
So I checked out if it was homogeneous and I found out that yes it is, of order 2.
So I called a new variable [itex]v=y/x[/itex].
After some algebra, I reached [itex]v(x)=Ae^{\int \frac{x^2-1}{x}dx}[/itex] where A is a constant. Now to get y(x), I'd multiply v(x) by x.
I'm not asking if my result is correct (I might have made some errors but overall I think the method does work. I'll check the result tomorrow since it's already too late), rather if there's a nicer or faster way to solve the exercise.
What would you have done in order to solve the DE?