```Date: Nov 30, 2012 6:40 PM
Author: Clyde Greeno @ MALEI
Subject: Re: Some important demonstrations on negative numbers

On careful analysis, "i" is simply the unit along the *image axis* (perpendicular to the *object axis*). It is only because of our interest in the ("cyclonic") combinations, a*(c,d) + b*(-d,c)  that the "multiplication" of "complexes" ... (a,b)*(c,d) ... results in (0,1)*(0,1) = (-1,0). In the non-symbolic form, "multiplication by i" simply amounts to counter-clockwise rotation by 90-degrees.- --------------------------------------------------From: "Robert Hansen" <bob@rsccore.com>Sent: Friday, November 30, 2012 4:42 PMTo: <math-teach@mathforum.org>Cc: <math-teach@mathforum.org>Subject: Re: Some important demonstrations on negative numbers> Doubled.>> Bob Hansen>> On Nov 30, 2012, at 5:01 PM, Jonathan Crabtree > <sendtojonathan@yahoo.com.au> wrote:>>>>>>> On Nov 29, 2012, at 4:20 PM, Jonathan Crabtree>> wrote:>>>>>>>> So what is i? I mean "i" as in the sqrt(-1), not>>> the>>>>> pronoun.>>>>>>>>>> Bob Hansen>>>>>>>> If you were to write the above using words only,>>> without both abbreviations and symbols, what would>>> you write?>>>>>>>>> What number multiplied by itself once then added to>>> one is zero?>>>>>> Bob Hansen>>>> OK thanks Bob. That was a great answer! Please keep playing along with >> the next question. You might even get your son to answer with just a >> single word...>>>> A number added to itself once, is said to have been WHAT?>>>> A number added to itself once, is said to have been...>>>> ==========>> Thank you!
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