Description: The second argument of a binary relation belongs to its range. (Contributed by NM, 13-Aug-2004)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | brelrn.1 | |- A e. _V |
|
| brelrn.2 | |- B e. _V |
||
| Assertion | brelrn | |- ( A C B -> B e. ran C ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | brelrn.1 | |- A e. _V |
|
| 2 | brelrn.2 | |- B e. _V |
|
| 3 | brelrng | |- ( ( A e. _V /\ B e. _V /\ A C B ) -> B e. ran C ) |
|
| 4 | 1 2 3 | mp3an12 | |- ( A C B -> B e. ran C ) |