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 ) ⊆ ran 𝐴 | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | resss | ⊢ ( 𝐴 ↾ 𝐵 ) ⊆ 𝐴 | |
| 2 | 1 | rnssi | ⊢ ran ( 𝐴 ↾ 𝐵 ) ⊆ ran 𝐴 |