Metamath Proof Explorer


Theorem riotaeqi

Description: Equal domains yield equal restricted iotas. Inference version. (Contributed by GG, 1-Sep-2025)

Ref Expression
Hypothesis riotaeqi.1 ⊢ 𝐴 = 𝐵
Assertion riotaeqi ( ℩ 𝑥 ∈ 𝐴 𝜑 ) = ( ℩ 𝑥 ∈ 𝐵 𝜑 )

Proof

Step Hyp Ref Expression
1 riotaeqi.1 ⊢ 𝐴 = 𝐵
2 biid ⊢ ( 𝜑 ↔ 𝜑 )
3 1 2 riotaeqbii ⊢ ( ℩ 𝑥 ∈ 𝐴 𝜑 ) = ( ℩ 𝑥 ∈ 𝐵 𝜑 )