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 ) |