Posts: 709
Threads: 104
Joined: Nov 2005
Quote:
Two main reasons:
1.
The uppercase/lowercase mixing of variables and function names between the CAS and Home screens is incredibly confusing. I've no idea how I could explain it to beginning students in a way which made it seem natural.
2.
I can't find an easy way to graph a function and its derivative. I can create a function in the CAS screen: x*(x^2-1) -> f(x) and compute its derivative diff(f(x),x) -> g(x) and then graph them with F1(X) = f('X') and F2(x) = g('X')
Why can't I just use F2(x) = diff(F1(x),x)?
1. This issue is just a matter of time. For me, it was very annoying at first. After getting used to it, it was hardly noticeable. Part of the reason for it, though, is to avoid conflicts with persistent global variables A-Z with symbolic manipulation (which generally substitutes a variable with its value if it is defined). So lower-case variables are generally undefined (unless the user defines them) which makes for much easier symbolic manipulation without having to use "restart" or "purge".
2. The lack of good documentation (although xcas has some decent documentation in French and English) made specifically for the HP Prime is where most of the blame should lie.
f(x):=x*(x^2-1);
F1:=f;
F2:=F1';
That's all you need to do before you hit the [Plot] button.
Cheers,
Han