Metamath Proof Explorer


Theorem aovnuoveq

Description: The alternative value of the operation on an ordered pair equals the operation's value at this ordered pair. (Contributed by Alexander van der Vekens, 26-May-2017)

Ref Expression
Assertion aovnuoveq
|- ( (( A F B )) =/= _V -> (( A F B )) = ( A F B ) )

Proof

Step Hyp Ref Expression
1 df-aov
 |-  (( A F B )) = ( F ''' <. A , B >. )
2 1 neeq1i
 |-  ( (( A F B )) =/= _V <-> ( F ''' <. A , B >. ) =/= _V )
3 afvnufveq
 |-  ( ( F ''' <. A , B >. ) =/= _V -> ( F ''' <. A , B >. ) = ( F ` <. A , B >. ) )
4 df-ov
 |-  ( A F B ) = ( F ` <. A , B >. )
5 3 1 4 3eqtr4g
 |-  ( ( F ''' <. A , B >. ) =/= _V -> (( A F B )) = ( A F B ) )
6 2 5 sylbi
 |-  ( (( A F B )) =/= _V -> (( A F B )) = ( A F B ) )