Metamath Proof Explorer


Theorem opelopab2

Description: Ordered pair membership in an ordered pair class abstraction. (Contributed by NM, 14-Oct-2007) (Revised by Mario Carneiro, 19-Dec-2013)

Ref Expression
Hypotheses opelopab2.1
|- ( x = A -> ( ph <-> ps ) )
opelopab2.2
|- ( y = B -> ( ps <-> ch ) )
Assertion opelopab2
|- ( ( A e. C /\ B e. D ) -> ( <. A , B >. e. { <. x , y >. | ( ( x e. C /\ y e. D ) /\ ph ) } <-> ch ) )

Proof

Step Hyp Ref Expression
1 opelopab2.1
 |-  ( x = A -> ( ph <-> ps ) )
2 opelopab2.2
 |-  ( y = B -> ( ps <-> ch ) )
3 1 2 sylan9bb
 |-  ( ( x = A /\ y = B ) -> ( ph <-> ch ) )
4 3 opelopab2a
 |-  ( ( A e. C /\ B e. D ) -> ( <. A , B >. e. { <. x , y >. | ( ( x e. C /\ y e. D ) /\ ph ) } <-> ch ) )