Description: Formula-building rule for restricted existential uniqueness quantifier. Deduction form. General version of reueqbidv . (Contributed by Zhi Wang, 20-Nov-2025)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | reueqbidva.1 | |- ( ph -> A = B ) |
|
| reueqbidva.2 | |- ( ( ph /\ x e. A ) -> ( ps <-> ch ) ) |
||
| Assertion | reueqbidva | |- ( ph -> ( E! x e. A ps <-> E! x e. B ch ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | reueqbidva.1 | |- ( ph -> A = B ) |
|
| 2 | reueqbidva.2 | |- ( ( ph /\ x e. A ) -> ( ps <-> ch ) ) |
|
| 3 | 2 | reubidva | |- ( ph -> ( E! x e. A ps <-> E! x e. A ch ) ) |
| 4 | 1 | reueqdv | |- ( ph -> ( E! x e. A ch <-> E! x e. B ch ) ) |
| 5 | 3 4 | bitrd | |- ( ph -> ( E! x e. A ps <-> E! x e. B ch ) ) |