MATLAB: How to define an ODE when there are some parameters are function of dependent variable

mupadodesymbolic

Hi,
I have this ODE, but I cannot figure out how to define it in MuPad or even in other symbolic ways:
    d/dx[D(y)*dy/dx] = R(y)
Where D and R are functions of y. I did not see any example in documents about such situations. In the final analytical solution terms like D(y'')dy'' may appear, so, maybe it is not possible to define such ODEs in MuPad (?).
I appreciate any help in advance.
EDITED: functions D(y) and R(y) are "unknown";they are just a function of y, but their functionality is not defined.

Best Answer

d/dx[D*dy/dx] = dD/dy*(dy/dx)^2 + D*d^2y/dx^2,
thus you have to solve the system
y1'=y2
y2'=(R(y1)-dD(y1)/dy1*(y2)^2)/D(y1)
This should be possible with every tool capable of solving ODEs.
Best wishes
Torsten.
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