Solving Second Order Inhomogeneous Equations with ODEs

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The discussion focuses on solving the second-order inhomogeneous differential equation d²y/dx² + k*dy/dx = du/dx + u. Participants highlight that traditional methods may not suffice due to the presence of multiple functions. The method of Frobenius is suggested as a potential approach, transforming the problem into a series solution. Additionally, reworking the equation into a partial differential equation is proposed to gain insights into the relationship between variables. Ultimately, using Laplace transforms can help derive a transfer function, but requires knowledge of the input function u(x) and initial conditions for y.
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d2y/dx2+k*dy/dx = du/dx+u

anyone got a hint how to use ODE to sovle this inhomogenous equation?

Thanks a lot
 
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You can't solve a single differential equation for two different functions any more than you can solve a single algebraic equation for two different numbers.
 
I would say that you may be able to solve this using the method of Frobenius, which ultimately means that you break it down into a root series problem. Although, I believe the person above me was correct in saying that you cannot solve this using traditional methods since you have three different variables.
 
hmm I wonder if its possibly to rework this into a partial differential equation for x that is a function of u and y, while not giving you a nice litle functionfor u and y it will give you a general idea of the solution.
 
This equation seems to represent a dynamic system, where u is the input and y the output.
You can use Laplace transforms to get a transfer function from u to y.
To solve for y you must know the function u(x) and the initial conditions y(0) and y'(0).
 

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