Metamath Proof Explorer


Theorem ffnaov

Description: An operation maps to a class to which all values belong, analogous to ffnov . (Contributed by Alexander van der Vekens, 26-May-2017)

Ref Expression
Assertion ffnaov
|- ( F : ( A X. B ) --> C <-> ( F Fn ( A X. B ) /\ A. x e. A A. y e. B (( x F y )) e. C ) )

Proof

Step Hyp Ref Expression
1 ffnafv
 |-  ( F : ( A X. B ) --> C <-> ( F Fn ( A X. B ) /\ A. w e. ( A X. B ) ( F ''' w ) e. C ) )
2 afveq2
 |-  ( w = <. x , y >. -> ( F ''' w ) = ( F ''' <. x , y >. ) )
3 df-aov
 |-  (( x F y )) = ( F ''' <. x , y >. )
4 2 3 eqtr4di
 |-  ( w = <. x , y >. -> ( F ''' w ) = (( x F y )) )
5 4 eleq1d
 |-  ( w = <. x , y >. -> ( ( F ''' w ) e. C <-> (( x F y )) e. C ) )
6 5 ralxp
 |-  ( A. w e. ( A X. B ) ( F ''' w ) e. C <-> A. x e. A A. y e. B (( x F y )) e. C )
7 6 anbi2i
 |-  ( ( F Fn ( A X. B ) /\ A. w e. ( A X. B ) ( F ''' w ) e. C ) <-> ( F Fn ( A X. B ) /\ A. x e. A A. y e. B (( x F y )) e. C ) )
8 1 7 bitri
 |-  ( F : ( A X. B ) --> C <-> ( F Fn ( A X. B ) /\ A. x e. A A. y e. B (( x F y )) e. C ) )