Metamath Proof Explorer


Theorem rabbida3

Description: Equivalent wff's yield equal restricted class abstractions. (Contributed by Glauco Siliprandi, 23-Oct-2021)

Ref Expression
Hypotheses rabbida3.1 xφ
rabbida3.2 φxAψxBχ
Assertion rabbida3 φxA|ψ=xB|χ

Proof

Step Hyp Ref Expression
1 rabbida3.1 xφ
2 rabbida3.2 φxAψxBχ
3 1 2 abbid φx|xAψ=x|xBχ
4 df-rab xA|ψ=x|xAψ
5 df-rab xB|χ=x|xBχ
6 3 4 5 3eqtr4g φxA|ψ=xB|χ