Theorem cbvriotavwOLD

Description: Obsolete version of cbvriotavw as of 30-Sep-2024. (Contributed by NM, 18-Mar-2013) (Revised by Gino Giotto, 26-Jan-2024) (Proof modification is discouraged.) (New usage is discouraged.)

	Ref	Expression
Hypothesis	cbvriotavwOLD.1	$$⊢x=y\to \left(\phi \leftrightarrow \psi \right)$$
Assertion	cbvriotavwOLD	$$⊢\left(\iota x\in A|\phi \right)=\left(\iota y\in A|\psi \right)$$

Proof

Step	Hyp	Ref	Expression
1		cbvriotavwOLD.1	$$⊢x=y\to \left(\phi \leftrightarrow \psi \right)$$
2		nfv	$$⊢Ⅎy\phi$$
3		nfv	$$⊢Ⅎx\psi$$
4	2 3 1	cbvriotaw	$$⊢\left(\iota x\in A|\phi \right)=\left(\iota y\in A|\psi \right)$$