Description: An image under the non-relation part of a class is empty. (Contributed by RP, 22-Oct-2020)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | imanonrel | |- ( ( A \ `' `' A ) " B ) = (/) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | df-ima | |- ( ( A \ `' `' A ) " B ) = ran ( ( A \ `' `' A ) |` B ) |
|
| 2 | resnonrel | |- ( ( A \ `' `' A ) |` B ) = (/) |
|
| 3 | 2 | rneqi | |- ran ( ( A \ `' `' A ) |` B ) = ran (/) |
| 4 | rn0 | |- ran (/) = (/) |
|
| 5 | 1 3 4 | 3eqtri | |- ( ( A \ `' `' A ) " B ) = (/) |