Description: A binary relation involving unordered triples. (Contributed by Scott Fenton, 7-Jun-2016)
Ref | Expression | ||
---|---|---|---|
Assertion | brtpid2 | |- A { C , <. A , B >. , D } B |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | opex | |- <. A , B >. e. _V |
|
2 | 1 | tpid2 | |- <. A , B >. e. { C , <. A , B >. , D } |
3 | df-br | |- ( A { C , <. A , B >. , D } B <-> <. A , B >. e. { C , <. A , B >. , D } ) |
|
4 | 2 3 | mpbir | |- A { C , <. A , B >. , D } B |