Description: Alternate definition of range. Definition 6.5(2) of TakeutiZaring p. 24. (Contributed by NM, 28-Dec-1996)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | dfrn3 | |- ran A = { y | E. x <. x , y >. e. A } | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | dfrn2 |  |-  ran A = { y | E. x x A y } | |
| 2 | df-br | |- ( x A y <-> <. x , y >. e. A ) | |
| 3 | 2 | exbii | |- ( E. x x A y <-> E. x <. x , y >. e. A ) | 
| 4 | 3 | abbii |  |-  { y | E. x x A y } = { y | E. x <. x , y >. e. A } | 
| 5 | 1 4 | eqtri |  |-  ran A = { y | E. x <. x , y >. e. A } |