[Request] for renaming variables

[Tim Wessman]

Quote:edit: the fact that dF1(x)/dx works seems to be logical after some thinking. Is it that the cas works with the function F1(X), replaces the -in the cas mode- X with

When you use the X, it is evaluating the real variable after. eg COS(X) <try to get a real value, can't so evalute the symbolic> -> COS(<current_num_in_variable>)

To evaluate a numerical derivative at a point, the syntax is d<fnc>/d<var>=<var>. eg: dF1(X)/(dX=X)