Is this solution valid for the original ODE?

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    Homogeneous Ode
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The discussion centers on the transformation of a first-order homogeneous ordinary differential equation (ODE) into a separable form. The original equation, du/dx = (2u^2)/x, where u = y/x, is manipulated to yield y^2 = -4x^2ln(Ax). The user questions the validity of their algebraic steps and the correctness of the final general solution, y = -x/(ln(Ax^2)). The conclusion confirms that the integration process was flawed, leading to an incorrect solution.

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wtmoore
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[Ok so I have transformed a
1st order homogenous ODE into a seperable ODE. However I am having trouble seperating to get y on it's own.

Here's the problem:

du/dx=(2u^2)/x where u = y/x

du/(2u^2)=dx/x <<can't get tex to work

-1/(4u^2)=ln(x)+C=ln(Ax) <<can't get tex to work

1=-4u^2ln(Ax)

1=-4(y^2/x^2)ln(Ax)

y^2=-4x^2ln(Ax)

y=i2xsqrt(lnAx)


Is this algebra correct? Is this the right solution? I'm not sure about bringing the y^2 over to the left is ok.
 
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I realize now, I messed up the integration.

The general solution is:

y=-x/(ln(Ax^2))
 

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