Description: Image of the empty set. Theorem 3.16(ii) of Monk1 p. 38. (Contributed by NM, 20-May-1998)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | ima0 | |- ( A " (/) ) = (/) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | df-ima | |- ( A " (/) ) = ran ( A |` (/) ) |
|
| 2 | res0 | |- ( A |` (/) ) = (/) |
|
| 3 | 2 | rneqi | |- ran ( A |` (/) ) = ran (/) |
| 4 | rn0 | |- ran (/) = (/) |
|
| 5 | 1 3 4 | 3eqtri | |- ( A " (/) ) = (/) |