Metamath Proof Explorer


Theorem refrelredund2

Description: The naive version of the definition of reflexive relation is redundant with respect to reflexive relation (see dfrefrel2 ) in equivalence relation. (Contributed by Peter Mazsa, 25-Oct-2022)

Ref Expression
Assertion refrelredund2
|- redund ( ( ( _I |` dom R ) C_ R /\ Rel R ) , RefRel R , EqvRel R )

Proof

Step Hyp Ref Expression
1 refrelredund4
 |-  redund ( ( ( _I |` dom R ) C_ R /\ Rel R ) , RefRel R , ( RefRel R /\ SymRel R ) )
2 df-eqvrel
 |-  ( EqvRel R <-> ( RefRel R /\ SymRel R /\ TrRel R ) )
3 3simpa
 |-  ( ( RefRel R /\ SymRel R /\ TrRel R ) -> ( RefRel R /\ SymRel R ) )
4 2 3 sylbi
 |-  ( EqvRel R -> ( RefRel R /\ SymRel R ) )
5 4 redundpim3
 |-  ( redund ( ( ( _I |` dom R ) C_ R /\ Rel R ) , RefRel R , ( RefRel R /\ SymRel R ) ) -> redund ( ( ( _I |` dom R ) C_ R /\ Rel R ) , RefRel R , EqvRel R ) )
6 1 5 ax-mp
 |-  redund ( ( ( _I |` dom R ) C_ R /\ Rel R ) , RefRel R , EqvRel R )