Consumer Reports likes Numworks

[Wes Loewer]

(10-22-2021 06:29 PM)celltx Wrote:  At least, one of their remark regarding the duplicated minus keys - a sign and an operator - remains valid for HP and Casio, as well as for TI. Indeed, it's hardly explainable legacy in modern algebraic-mode calculators.

I guess I fall in the other camp. I've often lamented the fact that the symbols for subtraction and negation look so similar. I wish they looked completely different from each other so that students would not confuse the two operations.

It's not unusual for a student to write something like d/dx e^cos(x) = e^cos(x)-sin(x). I have no way of knowing if they intended multiplication by a negative, or subtraction stemming from the error of adding the chain rule instead of multiplying. A different symbol would remove the ambiguity.

I prefer the way that TI enforces the different operations, while HP and Casio are more forgiving and will assume that a subtraction is really a negative if that makes more sense.

With most calculators, pressing a binary operator first, like +-*/^, generates Ans+, Ans-, Ans*, etc. With the NumWorks not having a separate negative key, all the operators work in the same manner except for subtraction. NumWorks assumes you are entering a negative number, which is logical if you don't have a separate negative key. Of course, you can manually enter ans-, but I prefer consistency. (I really hated how list processing on the 50g worked for all the math operators except +.)