Metamath Proof Explorer


Theorem nfopd

Description: Deduction version of bound-variable hypothesis builder nfop . This shows how the deduction version of a not-free theorem such as nfop can be created from the corresponding not-free inference theorem. (Contributed by NM, 4-Feb-2008)

Ref Expression
Hypotheses nfopd.2 ⊢ ( 𝜑 → Ⅎ 𝑥 𝐴 )
nfopd.3 ⊢ ( 𝜑 → Ⅎ 𝑥 𝐵 )
Assertion nfopd ( 𝜑 → Ⅎ 𝑥 ⟨ 𝐴 , 𝐵 ⟩ )

Proof

Step Hyp Ref Expression
1 nfopd.2 ⊢ ( 𝜑 → Ⅎ 𝑥 𝐴 )
2 nfopd.3 ⊢ ( 𝜑 → Ⅎ 𝑥 𝐵 )
3 nfaba1 ⊢ Ⅎ 𝑥 { 𝑧 ∣ ∀ 𝑥 𝑧 ∈ 𝐴 }
4 nfaba1 ⊢ Ⅎ 𝑥 { 𝑧 ∣ ∀ 𝑥 𝑧 ∈ 𝐵 }
5 3 4 nfop ⊢ Ⅎ 𝑥 ⟨ { 𝑧 ∣ ∀ 𝑥 𝑧 ∈ 𝐴 } , { 𝑧 ∣ ∀ 𝑥 𝑧 ∈ 𝐵 } ⟩
6 nfnfc1 ⊢ Ⅎ 𝑥 Ⅎ 𝑥 𝐴
7 nfnfc1 ⊢ Ⅎ 𝑥 Ⅎ 𝑥 𝐵
8 6 7 nfan ⊢ Ⅎ 𝑥 ( Ⅎ 𝑥 𝐴 ∧ Ⅎ 𝑥 𝐵 )
9 abidnf ⊢ ( Ⅎ 𝑥 𝐴 → { 𝑧 ∣ ∀ 𝑥 𝑧 ∈ 𝐴 } = 𝐴 )
10 9 adantr ⊢ ( ( Ⅎ 𝑥 𝐴 ∧ Ⅎ 𝑥 𝐵 ) → { 𝑧 ∣ ∀ 𝑥 𝑧 ∈ 𝐴 } = 𝐴 )
11 abidnf ⊢ ( Ⅎ 𝑥 𝐵 → { 𝑧 ∣ ∀ 𝑥 𝑧 ∈ 𝐵 } = 𝐵 )
12 11 adantl ⊢ ( ( Ⅎ 𝑥 𝐴 ∧ Ⅎ 𝑥 𝐵 ) → { 𝑧 ∣ ∀ 𝑥 𝑧 ∈ 𝐵 } = 𝐵 )
13 10 12 opeq12d ⊢ ( ( Ⅎ 𝑥 𝐴 ∧ Ⅎ 𝑥 𝐵 ) → ⟨ { 𝑧 ∣ ∀ 𝑥 𝑧 ∈ 𝐴 } , { 𝑧 ∣ ∀ 𝑥 𝑧 ∈ 𝐵 } ⟩ = ⟨ 𝐴 , 𝐵 ⟩ )
14 8 13 nfceqdf ⊢ ( ( Ⅎ 𝑥 𝐴 ∧ Ⅎ 𝑥 𝐵 ) → ( Ⅎ 𝑥 ⟨ { 𝑧 ∣ ∀ 𝑥 𝑧 ∈ 𝐴 } , { 𝑧 ∣ ∀ 𝑥 𝑧 ∈ 𝐵 } ⟩ ↔ Ⅎ 𝑥 ⟨ 𝐴 , 𝐵 ⟩ ) )
15 1 2 14 syl2anc ⊢ ( 𝜑 → ( Ⅎ 𝑥 ⟨ { 𝑧 ∣ ∀ 𝑥 𝑧 ∈ 𝐴 } , { 𝑧 ∣ ∀ 𝑥 𝑧 ∈ 𝐵 } ⟩ ↔ Ⅎ 𝑥 ⟨ 𝐴 , 𝐵 ⟩ ) )
16 5 15 mpbii ⊢ ( 𝜑 → Ⅎ 𝑥 ⟨ 𝐴 , 𝐵 ⟩ )