Theorem ax8v2 2111

Description: Second of two weakened versions of ax8v 2109, with an extra disjoint variable condition on 𝑦, 𝑧 see comments there. (Contributed by BJ, 7-Dec-2020.)

Assertion

Ref	Expression
ax8v2	⊢ (𝑥 = 𝑦 → (𝑥 ∈ 𝑧 → 𝑦 ∈ 𝑧))

Distinct variable groups:   𝑥,𝑦   𝑦,𝑧

Proof of Theorem ax8v2

Step	Hyp	Ref	Expression
1		ax8v 2109	1 ⊢ (𝑥 = 𝑦 → (𝑥 ∈ 𝑧 → 𝑦 ∈ 𝑧))

Syntax hints:   → wi 4

This theorem was proved from axioms:  ax-8 2108

This theorem is referenced by:  ax8  2112