Description: The range of a restriction is a subset of the whole range. (Contributed by Glauco Siliprandi, 17-Aug-2020)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | rnresss | |- ran ( A |` B ) C_ ran A |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | resss | |- ( A |` B ) C_ A |
|
| 2 | 1 | rnssi | |- ran ( A |` B ) C_ ran A |