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bkc82
Sep21-04, 09:22 PM
I didn't really know where to put this so, I put it here. Anyway in discreet mathematics what does the term max{x,y} mean? I can't find it in the book anywhere and the problem I'm trying to do says:

max{x,y} = (x+y+|x-y|)/2 for all real x,y

Note: I'm not asking you to do the problem I just want to know what max means.

Hurkyl
Sep21-04, 09:40 PM
If S is a set, then max S is simply the maximum element of S.

More precisely, max S = x iff:
x is in S
for all y in S: y <= x.


Note that max S is not always defined if S is an infinite set.

bkc82
Sep21-04, 09:53 PM
Thanks I appreciate it.

mathman
Sep21-04, 10:43 PM
The word for the mathematics you are talking about is spelled "discrete". The word "discreet" has to do with social behavior. For example if someone is dressed like a slob, it is discreet not to mention it in public.

HallsofIvy
Sep22-04, 07:42 AM
No, mathman the word is "discrete" in either sense. There is no (English) word spelled "discreet".

Muzza
Sep22-04, 08:42 AM
There is no (English) word spelled "discreet".


http://www.m-w.com/cgi-bin/dictionary?book=Dictionary&va=discreet&x=0&y=0

gazzo
Sep23-04, 12:31 AM
and in my little oxford lol. prudent; cautions in speech or action; unobtrusive.

HallsofIvy
Sep23-04, 06:36 AM
What? ME- Wrong?? How can this be allowed to happen!! I'm going to call Brittanica immediately and insist that they change the spelling!!