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Topic: Some important demonstrations on negative numbers
Replies: 70   Last Post: Dec 8, 2012 1:28 PM

 Messages: [ Previous | Next ]
 Paul A. Tanner III Posts: 5,920 Registered: 12/6/04
Re: Some important demonstrations on negative numbers
Posted: Nov 28, 2012 1:07 PM

On Wed, Nov 28, 2012 at 11:45 AM, Joe Niederberger
<niederberger@comcast.net> wrote:
...
> Let's look at negative numbers again. "Formally" we may write -1 < 0, and -1/1 = 1/-1. This perplexes mathematicians for a long time:
>
> http://www.ma.utexas.edu/users/mks/326K/Negnos.html
>
> One can say "just accept it, because it makes other things work out nicely". That's the "formal" approach.
>

Not to some of us. The formal approach is to prove it.

>
> Or one can attempt to understand it another way that grounds it in the everyday.

Or one can prove it (where "it" could be the more general -(a/b) =
a/(-b) for all elements in the set even if the set contains no
identity element).

Date Subject Author
11/27/12 Peter Duveen
11/27/12 James Elander
11/27/12 Robert Hansen
11/27/12 Joe Niederberger
11/27/12 Clyde Greeno @ MALEI
11/27/12 Robert Hansen
11/27/12 Peter Duveen
11/28/12 Robert Hansen
11/27/12 Joe Niederberger
11/27/12 Robert Hansen
11/27/12 Joe Niederberger
11/28/12 Robert Hansen
11/27/12 Joe Niederberger
11/28/12 GS Chandy
11/28/12 GS Chandy
11/28/12 Robert Hansen
11/28/12 Peter Duveen
11/28/12 Robert Hansen
11/28/12 Robert Hansen
11/29/12 kirby urner
11/28/12 Peter Duveen
11/28/12 syeds
11/28/12 GS Chandy
11/28/12 Joe Niederberger
11/28/12 Paul A. Tanner III
11/28/12 Robert Hansen
11/29/12 kirby urner
11/28/12 Joe Niederberger
11/29/12 Paul A. Tanner III
11/28/12 Jonathan J. Crabtree
11/28/12 Joe Niederberger
11/29/12 Robert Hansen
11/28/12 Joe Niederberger
11/29/12 Peter Duveen
11/29/12 Peter Duveen
11/29/12 Joe Niederberger
11/30/12 Robert Hansen
11/29/12 Joe Niederberger
11/29/12 Joe Niederberger
11/29/12 Peter Duveen
11/29/12 Joe Niederberger
11/29/12 Jonathan J. Crabtree
11/29/12 Robert Hansen
11/29/12 Jonathan J. Crabtree
11/30/12 Robert Hansen
11/29/12 Joe Niederberger
11/30/12 Joe Niederberger
11/30/12 Robert Hansen
11/30/12 Joe Niederberger
11/30/12 Robert Hansen
11/30/12 Joe Niederberger
11/30/12 Robert Hansen
11/30/12 Joe Niederberger
11/30/12 Jonathan J. Crabtree
11/30/12 Robert Hansen
11/30/12 Clyde Greeno @ MALEI
11/30/12 Joe Niederberger
11/30/12 Clyde Greeno @ MALEI
11/30/12 Robert Hansen
12/1/12 Robert Hansen
11/30/12 Robert Hansen
11/30/12 Clyde Greeno
12/1/12 Robert Hansen
11/30/12 Jonathan J. Crabtree
12/1/12 Joe Niederberger
12/1/12 Robert Hansen
12/8/12 Clyde Greeno @ MALEI
12/1/12 Joe Niederberger
12/2/12 Jonathan J. Crabtree
12/2/12 Clyde Greeno @ MALEI
12/3/12 Robert Hansen