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rushhour
12-16-2008, 09:17 AM
Hi,

I have the following relation (click on link to view):

http://e.imagehost.org/0187/relation.jpg

And I need help giving a mathmatical definition of this relation. I am also having problems stating if the relation is reflexive, symmetric, transitive or antisymmetric. I also need to state my reasons for this. Another problem I am having is stating whether this is a partial order or an equivalence relation.

Any help would be good.

Thanks in advance if you can help me. (That is of course if anyone actually knows anything about discrete maths.)

laserlight
12-16-2008, 09:27 AM
This may be the General Discussions forum, but seeing that it is pretty much a homework question, the homework policy (http://cboard.cprogramming.com/announcement.php?f=3&a=39) applies ;)

tabstop
12-16-2008, 11:33 AM
If you understand what the picture means, then you should be golden. I would guess that (x,y) is an element of your relation R iff there's an arrow from x to y. From there checking all your definitions for reflexive etc. is trivial.

zacs7
12-16-2008, 03:37 PM
> That is of course if anyone actually knows anything about discrete maths.
That's like asking, does anyone here know anything about computer science?

If you look-up the definitions of reflexive, symmetric, transitive and antisymmetric then you'll get the answer to whether it's a partial or total ordering. Knowing that will also help you find a relation.