High School First Order Non-Linear ODE (what method to use?)

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The discussion revolves around solving the first-order non-linear ordinary differential equation dy/dx = −[2x + ln(y)]*(y/x). Initial attempts to classify the equation revealed it is not exact, separable, homogeneous, or linear, complicating the solution process. Suggestions include exploring potential solutions like a^x or substituting y with an exponential function, y = e^t, to simplify the equation. A proposed method involves using y = exp(qx) to achieve separation, leading to a solution form where q = (A/x^2) - 1. The conversation emphasizes the importance of substitution and integration techniques in tackling non-linear ODEs.
Apothem
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Hi,

The problem is to solve:
dy/dx = −[2x + ln(y)]*(y/x)

Attempt:
I have tried to see if it is exact, I found it not to be, I can't easily find a function to multiply by to make it exact either (unless I am missing something obvious). It clearly isn't seperable, nor is it homogenous (I know although some non-homogenous ODEs can be solved using the homogenous method I don't think this one can be), it also isn't a linear equation so we can't use integrating factors.

I'm looking for pointers in the right direction/which method to use.

Thanks for your time
 
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Have you tried guessing a solution?

Something like ##a^x## or something that works well with the natural log function.
 
I think you are going the right way; checking the exact form, homogeneity etc.
Here since there is a logarithmic function, I recommend substituting y=et where t is parameter and then be solved by finding integrating factor.
 
Using y = exp(qx), where q is a function of x , I got it to separate, giving
q = (A/x2) - 1, where A is a constant of integration.
It seems to check.
 

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