Description: Equivalent wff's yield equal restricted class abstractions. (Contributed by Glauco Siliprandi, 23-Oct-2021)
Ref | Expression | ||
---|---|---|---|
Hypotheses | rabbida3.1 | |- F/ x ph |
|
rabbida3.2 | |- ( ph -> ( ( x e. A /\ ps ) <-> ( x e. B /\ ch ) ) ) |
||
Assertion | rabbida3 | |- ( ph -> { x e. A | ps } = { x e. B | ch } ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | rabbida3.1 | |- F/ x ph |
|
2 | rabbida3.2 | |- ( ph -> ( ( x e. A /\ ps ) <-> ( x e. B /\ ch ) ) ) |
|
3 | 1 2 | abbid | |- ( ph -> { x | ( x e. A /\ ps ) } = { x | ( x e. B /\ ch ) } ) |
4 | df-rab | |- { x e. A | ps } = { x | ( x e. A /\ ps ) } |
|
5 | df-rab | |- { x e. B | ch } = { x | ( x e. B /\ ch ) } |
|
6 | 3 4 5 | 3eqtr4g | |- ( ph -> { x e. A | ps } = { x e. B | ch } ) |