Possible error in on-calculator help.

[pwarmuth]

The help file contradicts what parisse said in his quote, and I trust his word on it being as he is the one who programmed it. The content in that help file led to be believe there were inconsistencies in the way the cas evaluated rational roots. If you take 3 NTHROOT -1 (this is the what you get when you use [SHIFT] x^y) it returns -1. If you take (-1)^(1/3) it returns (1/2)*sqrt(3)*i+(1/2) regardless of what he complex mode (i) setting is.

"[T]he complex mode setting (note that this is named i on the Prime CAS settings, complex on the Prime is the complex variable mode setting). If you keep complex mode [use i] unchecked, it does not mean you will stay in the real domain. " -parisse

For example, even with the option for i turned off, if you ask for sqrt(-1) it will return i. This is by definition not a real number.

Also, according to parisse, the 'complex' checkbox instructs the CAS that factor and associated functions should behave as if coefficients are complex even if they are all reals.

Once again, the content in the help file states the following:

*Use i: If checked, the calculator is in complex mode and complex solutions will be displayed when they exist. If not checked, the calculator is in real mode and only real solutions will be displayed.

One of these things is not like the other.