Description: Equivalent wff's yield equal restricted definition binders (deduction form). ( raleqbidva analog.) (Contributed by Thierry Arnoux, 29-Jan-2025)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | riotaeqbidva.1 | ⊢ ( 𝜑 → 𝐴 = 𝐵 ) | |
| riotaeqbidva.2 | ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → ( 𝜓 ↔ 𝜒 ) ) | ||
| Assertion | riotaeqbidva | ⊢ ( 𝜑 → ( ℩ 𝑥 ∈ 𝐴 𝜓 ) = ( ℩ 𝑥 ∈ 𝐵 𝜒 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | riotaeqbidva.1 | ⊢ ( 𝜑 → 𝐴 = 𝐵 ) | |
| 2 | riotaeqbidva.2 | ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → ( 𝜓 ↔ 𝜒 ) ) | |
| 3 | 2 | riotabidva | ⊢ ( 𝜑 → ( ℩ 𝑥 ∈ 𝐴 𝜓 ) = ( ℩ 𝑥 ∈ 𝐴 𝜒 ) ) |
| 4 | 1 | riotaeqdv | ⊢ ( 𝜑 → ( ℩ 𝑥 ∈ 𝐴 𝜒 ) = ( ℩ 𝑥 ∈ 𝐵 𝜒 ) ) |
| 5 | 3 4 | eqtrd | ⊢ ( 𝜑 → ( ℩ 𝑥 ∈ 𝐴 𝜓 ) = ( ℩ 𝑥 ∈ 𝐵 𝜒 ) ) |