Metamath Proof Explorer


Theorem iscnrm3lem5

Description: Lemma for iscnrm3l . (Contributed by Zhi Wang, 3-Sep-2024)

Ref Expression
Hypotheses iscnrm3lem5.1 ⊢ x = S ∧ y = T → φ ↔ ψ
iscnrm3lem5.2 ⊢ x = S ∧ y = T → χ ↔ θ
iscnrm3lem5.3 ⊢ τ ∧ η ∧ ζ → S ∈ V ∧ T ∈ W
iscnrm3lem5.4 ⊢ τ ∧ η ∧ ζ → ψ → θ → σ
Assertion iscnrm3lem5 ⊢ τ → ∀ x ∈ V ∀ y ∈ W φ → χ → η → ζ → σ

Proof

Step Hyp Ref Expression
1 iscnrm3lem5.1 ⊢ x = S ∧ y = T → φ ↔ ψ
2 iscnrm3lem5.2 ⊢ x = S ∧ y = T → χ ↔ θ
3 iscnrm3lem5.3 ⊢ τ ∧ η ∧ ζ → S ∈ V ∧ T ∈ W
4 iscnrm3lem5.4 ⊢ τ ∧ η ∧ ζ → ψ → θ → σ
5 1 2 imbi12d ⊢ x = S ∧ y = T → φ → χ ↔ ψ → θ
6 5 rspc2gv ⊢ S ∈ V ∧ T ∈ W → ∀ x ∈ V ∀ y ∈ W φ → χ → ψ → θ
7 6 3 4 iscnrm3lem4 ⊢ τ → ∀ x ∈ V ∀ y ∈ W φ → χ → η → ζ → σ