Description: Equality deduction for the set-like predicate. (Contributed by Matthew House, 10-Sep-2025)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | seeq12d.1 | |- ( ph -> R = S ) | |
| seeq12d.2 | |- ( ph -> A = B ) | ||
| Assertion | seeq12d | |- ( ph -> ( R Se A <-> S Se B ) ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | seeq12d.1 | |- ( ph -> R = S ) | |
| 2 | seeq12d.2 | |- ( ph -> A = B ) | |
| 3 | seeq1 | |- ( R = S -> ( R Se A <-> S Se A ) ) | |
| 4 | seeq2 | |- ( A = B -> ( S Se A <-> S Se B ) ) | |
| 5 | 3 4 | sylan9bb | |- ( ( R = S /\ A = B ) -> ( R Se A <-> S Se B ) ) | 
| 6 | 1 2 5 | syl2anc | |- ( ph -> ( R Se A <-> S Se B ) ) |