solve() problems

[HansB]

Thanks for all the good advise!

If I investigate polynomials in the Function app, the Symb view uses and demands a upper-case X in the expressions. The Plot view gives the functions as nice plots, and I can even get numerical solutions for Root through soft keys Menu -> Fcn, but only one at a time, and I need to trace via cursor keys to get other solutions.

But in symb view I can copy a function, and paste it into Home screen, and there use solve(''), for instance solve('X^2 +X-1'), which gives me the numerical Root solutions. solve() assumed I wanted the roots, i.e. X^2 +X-1=0. But if I paste the function into CAS and use solve(), I get a syntax error, and have to change the case of all X from upper to lower. Then it works, with a warning that it is not an equation, and assumes it to be =0. And then I get the exact algebraic root solutions to the polynomial function. This is great too, but it is a much more cumbersome process, having to edit each function pasted, to convert all upper case X to lower case x! The CAS mode seems the more logical way to do such investigations, but it does not communicate too well with Symb view in Function app, it seems, or rather vice versa. All because of X <-> x differences.

It would be cool in Function Plot view to get solutions to Root etc not only numerical, but, at a press of a soft button, also algebraic. Another quibble I got with the Function app is this: investigating a function in Plot view and tracing it and for instance finding a Root via the soft menu, the tracer is put onto the solution, the solution is given numerically, but if I then jump to another graphed function via up/down cursor keys, the trace cursor is not at precisely the same X anymore, so the F(X) values are not quite comparable. It would be nice if they were!