Description: Equivalent wff's yield equal restricted class abstractions. (Contributed by Thierry Arnoux, 4-Feb-2017)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | rabbidva2.1 | ||
| Assertion | rabbidva2 |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | rabbidva2.1 | ||
| 2 | 1 | abbidv | |
| 3 | df-rab | ||
| 4 | df-rab | ||
| 5 | 2 3 4 | 3eqtr4g |