Show that a relation R on a set X is symmetric if and only if whenever there is a directed edge from x to y in the digraph of R, there is a directed edge from y to x in the digraph of R.(i don't have the slightest idea how to do this...)

Results 1 to 2 of 2

- August 9th 2006, 05:06 AM #1

- Joined
- Aug 2006
- Posts
- 12

- August 9th 2006, 08:46 AM #2

- Joined
- Nov 2005
- From
- New York City
- Posts
- 10,616
- Thanks
- 10

Originally Posted by**kodirl**

Therefore, you can talk about G=(X,R) as a graph. But since R is symmetric on X you have that xy is in R (that means an edge in this digraph) means that yx is in E(G) too because of symetrry (that means an edge in this digraph).