
Re: Some important demonstrations on negative numbers
Posted:
Nov 30, 2012 6:40 PM


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 nonsymbolic form, "multiplication by i" simply amounts to counterclockwise rotation by 90degrees.   From: "Robert Hansen" <bob@rsccore.com> Sent: Friday, November 30, 2012 4:42 PM To: <mathteach@mathforum.org> Cc: <mathteach@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!

