Find general solution, 1st order ODE

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2h2o
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Homework Statement



Find a general solution.

Homework Equations



[tex]2x\frac{dy}{dx}+y^{3}e^{-2x}=2xy[/tex]

The Attempt at a Solution



Looks like a Bernoulli equation to me, after some algebra:

[tex]\frac{dy}{dx}+\frac{y^{3}}{2xe^{2x}}=y[/tex]

[tex]\frac{dy}{dx}+\frac{y}{2xe^{2x}}=y^{-1}[/tex]

so with [tex]n=-1[/tex]
[tex]v=y^{2}, y=v^{1/2}, \frac{dy}{dx}=\frac{1}{2}v^{-1/2}\frac{dv}{dx}[/tex]

[tex]\frac{1}{2}v^{-1/2}}\frac{dv}{dx}+\frac{v^{1/2}}{2xe^{2x}}=v^{-1/2}[/tex]

[tex]\frac{1}{2}\frac{dv}{dx}+\frac{v}{2xe^{2x}}=1[/tex]

[tex]\frac{dv}{dx}+\frac{v}{xe^{2x}}=2[/tex]

Now an integrating factor:

[tex]\mu=exp[\int{x^{-1}e^{-2x}dx}][/tex]

And that's where I get stuck. This doesn't look like any elementary integral I've learned how to solve, and wolfram|alpha gives me something called the "exponential integral" which we haven't been taught. So I've done something wrong, but I don't see it.

Thanks for any insights.
 
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Ok, I think I found my error: I forgot to divide the dy/dx by y^2 when I obtained y^-1 as the RHS. No wonder I wound up with a nonelementary integral. However, I'm still stuck.

I don't recognize this equation, and manipulating it around trying to "force it" to be in first-order linear, homogeneous, or bernoulli hasn't helped. So I'm stuck.

This is where I am, and don't recognize it:

[tex]\frac{dy}{dx}+\frac{y^{3}}{2xe^{2x}}=y[/tex]
 
Isn't that separable? Split up the differentials?