Description: Equivalent wff's yield equal restricted class abstractions. (Contributed by Glauco Siliprandi, 23-Oct-2021)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | rabbida3.1 | ||
| rabbida3.2 | |||
| Assertion | rabbida3 |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | rabbida3.1 | ||
| 2 | rabbida3.2 | ||
| 3 | 1 2 | abbid | |
| 4 | df-rab | ||
| 5 | df-rab | ||
| 6 | 3 4 5 | 3eqtr4g |