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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

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Robert Hansen

Posts: 7,528
From: Florida
Registered: 6/22/09
Re: In "square root of -1", should we say "minus 1" or "negative 1"?
Posted: Dec 4, 2012 11:07 AM
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On Dec 4, 2012, at 10:40 AM, Joe Niederberger <niederberger@comcast.net> wrote:

> 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



I was thinking subtracting twice, not the product of signs. Like, "What is zero minus a minus 3?"

Bob Hansen



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