I'm having trouble with the following:(adsbygoogle = window.adsbygoogle || []).push({});

Let R be a relation on A. Prove that if Dom(R) [itex]\bigcap[/itex] Range(R) = ø, then R is transitive.

I took the negation of the "R is transitive" to try proof by contrapositive (as the professor suggested), and have the following:

[itex]\exists[/itex] x,y,z [itex]\in[/itex] A s.t. (x,y) [itex]\in[/itex] R [itex]\wedge[/itex] (y,z)[itex]\in[/itex] R [itex]\wedge[/itex] (x,z) [itex]\notin[/itex] R.

Now I am stuck

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# Sets - Relations - proof involving transitivity

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