ODE solve help : predefine a function

Not sure if I understand correctly what you want to achieve,

I wonder why you would want to introduce a third unknown function in the solve block which is dependent in a simple way on the function N.p which you are solving for.

Are you looking for something like this:

Hi,

I think it is getting a bit deviated from i want to achieve.. I don't want to add an extra M.p on the ODE block, I am only trying to simplify my equations.

What i trying to achieve is to make the C.p(t) equation look a bit simple by shrinking ((1-delta2)*P.N' N.p(t)) into one variable such as M.p(t).

such as to predefine a variable,

M.p(t) = (1-delta).P.N*N.p(t)

So that,

C.p(t) = M.p(t) - µ.pCp(t)

or if this is possible?