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From: betel@buhub.bradley.edu (Robert Crawford)
Subject: Re: Why sqrt(-1)=j and not sqrt(-1)=i
Message-ID: <1991Apr30.154605.29904@bradley.bradley.edu>
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Date: Tue, 30 Apr 91 15:46:05 GMT
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jhoward@helps.cactus.org (James Howard) writes:

>In math the sqrt(-1) is representated by the letter i.  In electronics
>why is the letter j used to represent the square root of -1?

	It has to do with the assignment of "direction vectors". I.e.
8i + 4j is 8 units along the x-axis and 4 units along the y-axis. Now,
if you look at the complex number plane, the imaginary part is graphed
along the "y-axis".

	The use of i comes from an abbreviation for "imaginary". j is
a better term, since you can then treat complex numbers as vectors and
do cross and dot products...
-- 
Rob Crawford		        \"You can have peace. Or you
betel@buhub.bradley.edu	          \can have freedom. Don't ever
Dum vivimus, vivamus!               \count on having both at once."
--
Rob Crawford		        \"You can have peace. Or you
betel@buhub.bradley.edu	          \can have freedom. Don't ever
Dum vivimus, vivamus!               \count on having both at once."