Theorem opvtxfvi

Description: The set of vertices of a graph represented as an ordered pair of vertices and indexed edges as function value. (Contributed by AV, 4-Mar-2021)

	Ref	Expression
Hypotheses	opvtxfvi.v	|- V e. _V
	opvtxfvi.e	|- E e. _V
Assertion	opvtxfvi	|- ( Vtx ` <. V , E >. ) = V

Proof

Step	Hyp	Ref	Expression
1		opvtxfvi.v	|- V e. _V
2		opvtxfvi.e	|- E e. _V
3		opvtxfv	|- ( ( V e. _V /\ E e. _V ) -> ( Vtx ` <. V , E >. ) = V )
4	1 2 3	mp2an	|- ( Vtx ` <. V , E >. ) = V