Description: Equality theorem for ordered pairs. (Contributed by NM, 28-May-1995)
Ref | Expression | ||
---|---|---|---|
Assertion | opeq12 | |- ( ( A = C /\ B = D ) -> <. A , B >. = <. C , D >. ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | opeq1 | |- ( A = C -> <. A , B >. = <. C , B >. ) |
|
2 | opeq2 | |- ( B = D -> <. C , B >. = <. C , D >. ) |
|
3 | 1 2 | sylan9eq | |- ( ( A = C /\ B = D ) -> <. A , B >. = <. C , D >. ) |