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Topic: Please remind me why -3^2 = -9
Replies: 26   Last Post: Nov 18, 2012 7:51 PM

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 Alain Schremmer Posts: 876 Registered: 10/10/05
Re: Please remind me why -3^2 = -9
Posted: Oct 19, 2012 5:15 PM

On Oct 19, 2012, at 12:22 PM, Clyde Greeno wrote:

> A Mackey-prompted extension:
>
> "Below, insert parens to show two reasonable interpretations of '-
> x^y' ... and circle the one that is most commonly used in
> mathematical literature:
> -x^y or -x^y "
> ... then illustrate the difference, by evaluating both formulas, by
> choosing a value for x, and a value for y, and using those values in
> each of your two parenthesized formulas. Which of those values is
> displayed by your calculator ... with and without your parens "

Indeed, even nicer.

I find it interesting that I very rarely have that kind of idea. But
then that's why people collaborate. Too bad, though, that mathematics
"educators" usually don't even want to consider the possibility.

Regards
--schremmer
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Date Subject Author
10/18/12 Phil Mahler
10/18/12 John Peterson
10/18/12 Guy Brandenburg
10/18/12 Wayne Mackey
10/18/12 Phil Mahler
10/18/12 RotmanJ
10/18/12 Paul Hertzel
10/18/12 Phil Mahler
10/18/12 Clyde Greeno
10/19/12 Clyde Greeno
10/19/12 Alain Schremmer
10/19/12 Wayne Mackey
10/19/12 Alain Schremmer
10/19/12 Clyde Greeno
10/19/12 Alain Schremmer
10/21/12 Wayne Mackey
11/14/12 Beth Hentges
11/15/12 Clyde Greeno
11/16/12 Alain Schremmer
10/18/12 Collinge, Peter (Mathematics)
10/18/12 Guy Brandenburg
10/18/12 Phil Mahler
10/18/12 Alain Schremmer
11/18/12 EddieC
11/18/12 Matthews, George
11/18/12 Phil Mahler
11/18/12 Alain Schremmer