Casio anomaly or gremlin or bug...

[pier4r]

(09-05-2017 06:20 PM)Matt Agajanian Wrote:  So, you're saying the TI and HP results are correct? What rules are present when +/- or x/: are on the same level in an expression?

Those questions (that are a bit embarrassing sometimes) rely on the fact that people hold different knowledge about conventions (and then they fight for it).

A convention is defined by one or more people, then people sticks to it and a result is given. So the "correct" part is valid only if one follows the mainstream convention.

If I decide that addition come first and subtraction comes after, of course the result "1" (or 9) is wrong, but because I am using a convention that is valid for myself only.

So defining a convention and sticking to it makes the result unambiguous.


Also in Europe, as far as I know, the mainstream definition is:

parentheses (from innermost to outmost)
exponentiation and roots (leftmost first. That is, the operation that happens first on the left of the expression gets evaluated)
multiplication or division (which one first? Left first)
addition and subtraction (leftmost first)

translating 6/2(1+2) in RPN it would be (RPN is really neat to show what I do first)
1
2
+
6
2
/
*

thus 9.

For instance
(1+2)2/6

would be
1
2
+
2
*
6
/