Metamath Proof Explorer


Theorem rabeqi

Description: Equality theorem for restricted class abstractions. Inference form of rabeqf . (Contributed by Glauco Siliprandi, 26-Jun-2021) Avoid ax-10 , ax-11 , ax-12 . (Revised by Gino Giotto, 3-Jun-2024)

Ref Expression
Hypothesis rabeqi.1 𝐴 = 𝐵
Assertion rabeqi { 𝑥𝐴𝜑 } = { 𝑥𝐵𝜑 }

Proof

Step Hyp Ref Expression
1 rabeqi.1 𝐴 = 𝐵
2 1 eleq2i ( 𝑥𝐴𝑥𝐵 )
3 2 anbi1i ( ( 𝑥𝐴𝜑 ) ↔ ( 𝑥𝐵𝜑 ) )
4 3 rabbia2 { 𝑥𝐴𝜑 } = { 𝑥𝐵𝜑 }