Description: Alternate definition of range. (Contributed by Peter Mazsa, 1-Aug-2018)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | dfrn6 | |- ran R = { x | [ x ] `' R =/= (/) } |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | df-rn | |- ran R = dom `' R |
|
| 2 | dfdm6 | |- dom `' R = { x | [ x ] `' R =/= (/) } |
|
| 3 | 1 2 | eqtri | |- ran R = { x | [ x ] `' R =/= (/) } |