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Relations  Date: 03/23/2003 at 15:24:36 From: John Subject:
Discrete Maths, specifically, relations   - reflexive and
antisymmetric? - irreflexive and symmetric?  First, I'm having
trouble understanding what relation is. When you say  relation
do you just mean a relationship between a and b? e.g. (a,b)
belong to R and so do (e,f). Are (a,b) and (e,f) two relations
or the  same one (since they both belong to R)?  Date:
03/24/2003 at 04:48:21 From: Doctor Jacques Subject: Re:
Discrete Maths, specifically, relations  Hi John,  A relation on
a set A is just a set of pairs of elements of A, i.e.
expressions (x,y) where x and y are elements of A (possibly the
same).  Note that we consider ordered pairs - (x,y) is not the
same as (y,x).  An important point is that you can define
relations quite arbitrarily.  For every possible pair (x,y), you
can decide whether or not you  include it in the