Rayleigh-Ritz/Galerkin method with MC14 and ODESolve

Charles Picard wrote: Hello MathCad community, I need to copy and paste the differential equations in the "Given" area to make it work on another sheet. What i need is to not have that copy and paste, hence the following. How can i achieve that?

Sorry You have use functions in the Given block and must copy and paste equations with this functions.

Maybe you post the worksheet with the workin ODEsolve, too.

Think it would be better not to protect the vital regions.

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Not sure what the main question is as I am still confused about the "copy to another sheet"!?

As I see that the Odesolve throws an error, maybe doing as follows will do the job - I didn't wait for ODEsolve to finish, though.

Notice that instead of Ec1 OF second derivative we have now Ec1 of 1 TIMES the second derivative, etc.

Looks like Mathcad doesn't like the second derivatives to be arguments of functions. Could be thats because the function is defined by a symbolic evaluation but I guess Mathcad doesn't like any function there.

Just tried it - you cannot put the derivative as argument of any function here.

Of course the workarund given will only work for that specific kind of function Ec with the result that Ec1,2,3(x) is just a multiple of x.