Description: A function's value belongs to its range. (Contributed by NM, 15-Oct-1996)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | fnfvelrn | |- ( ( F Fn A /\ B e. A ) -> ( F ` B ) e. ran F ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | fvelrn | |- ( ( Fun F /\ B e. dom F ) -> ( F ` B ) e. ran F ) |
|
| 2 | 1 | funfni | |- ( ( F Fn A /\ B e. A ) -> ( F ` B ) e. ran F ) |