Metamath Proof Explorer


Theorem refrelredund3

Description: The naive version of the definition of reflexive relation ( A. x e. dom R x R x /\ Rel R ) is redundant with respect to reflexive relation (see dfrefrel3 ) in equivalence relation. (Contributed by Peter Mazsa, 25-Oct-2022)

Ref Expression
Assertion refrelredund3
|- redund ( ( A. x e. dom R x R x /\ Rel R ) , RefRel R , EqvRel R )

Proof

Step Hyp Ref Expression
1 refrelredund2
 |-  redund ( ( ( _I |` dom R ) C_ R /\ Rel R ) , RefRel R , EqvRel R )
2 idrefALT
 |-  ( ( _I |` dom R ) C_ R <-> A. x e. dom R x R x )
3 2 anbi1i
 |-  ( ( ( _I |` dom R ) C_ R /\ Rel R ) <-> ( A. x e. dom R x R x /\ Rel R ) )
4 3 redundpbi1
 |-  ( redund ( ( ( _I |` dom R ) C_ R /\ Rel R ) , RefRel R , EqvRel R ) <-> redund ( ( A. x e. dom R x R x /\ Rel R ) , RefRel R , EqvRel R ) )
5 1 4 mpbi
 |-  redund ( ( A. x e. dom R x R x /\ Rel R ) , RefRel R , EqvRel R )