Metamath Proof Explorer


Theorem cnvepres

Description: Restricted converse epsilon relation as a class of ordered pairs. (Contributed by Peter Mazsa, 10-Feb-2018)

Ref Expression
Assertion cnvepres
|- ( `' _E |` A ) = { <. x , y >. | ( x e. A /\ y e. x ) }

Proof

Step Hyp Ref Expression
1 dfres2
 |-  ( `' _E |` A ) = { <. x , y >. | ( x e. A /\ x `' _E y ) }
2 brcnvep
 |-  ( x e. _V -> ( x `' _E y <-> y e. x ) )
3 2 elv
 |-  ( x `' _E y <-> y e. x )
4 3 anbi2i
 |-  ( ( x e. A /\ x `' _E y ) <-> ( x e. A /\ y e. x ) )
5 4 opabbii
 |-  { <. x , y >. | ( x e. A /\ x `' _E y ) } = { <. x , y >. | ( x e. A /\ y e. x ) }
6 1 5 eqtri
 |-  ( `' _E |` A ) = { <. x , y >. | ( x e. A /\ y e. x ) }