Metamath Proof Explorer


Theorem exanres2

Description: Equivalent expressions with existential quantification. (Contributed by Peter Mazsa, 10-Sep-2021)

Ref Expression
Assertion exanres2
|- ( ( B e. V /\ C e. W ) -> ( E. u ( u ( R |` A ) B /\ u ( S |` A ) C ) <-> E. u e. A ( B e. [ u ] R /\ C e. [ u ] S ) ) )

Proof

Step Hyp Ref Expression
1 exanres
 |-  ( ( B e. V /\ C e. W ) -> ( E. u ( u ( R |` A ) B /\ u ( S |` A ) C ) <-> E. u e. A ( u R B /\ u S C ) ) )
2 exanres3
 |-  ( ( B e. V /\ C e. W ) -> ( E. u e. A ( B e. [ u ] R /\ C e. [ u ] S ) <-> E. u e. A ( u R B /\ u S C ) ) )
3 1 2 bitr4d
 |-  ( ( B e. V /\ C e. W ) -> ( E. u ( u ( R |` A ) B /\ u ( S |` A ) C ) <-> E. u e. A ( B e. [ u ] R /\ C e. [ u ] S ) ) )