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Topic: Re: In "square root of -1", should we say "minus 1" or "negative
1"?

Replies: 1   Last Post: Dec 4, 2012 11:07 AM

 Messages: [ Previous | Next ]
 Joe Niederberger Posts: 4,657 Registered: 10/12/08
Re: In "square root of -1", should we say "minus 1" or "negative
1"?

Posted: Dec 4, 2012 10:40 AM

R. Hansen says:
- -----------------------------------------
I was thinking...
(3) * (-2) = (-2) + (-2) + (-2) = -2 - 2 - 2
Or the other way around ...
(-2) * (3) = - 3 - 3 (repeated subtraction) (I just realized so much for crabtree's subtracted once from itself theory, that was an unexpected bonus)
And with two negatives...
(-2) * (-3) = - (-3) - (-3) (thus, when you are subtracting a minus you are actually adding)
- ----------------------------------------------

That's kind of cute -- I like it.
But I think to make it solid you would have to
define multiplication of (+)x(-) and (-)x(+)
first, and treat them asymmetrically!

Cheers,
Joe N

Date Subject Author
12/4/12 Joe Niederberger
12/4/12 Robert Hansen