Theorem or2expropbilem1 48307

Description: Lemma 1 for or2expropbi 48309 and ich2exprop 48758. (Contributed by AV, 16-Jul-2023.)

Assertion

Ref	Expression
or2expropbilem1	⊢ ((𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → ((𝐴 = 𝑎 ∧ 𝐵 = 𝑏) → (𝜑 → ∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ [𝑦 / 𝑏][𝑥 / 𝑎]𝜑))))

Distinct variable groups:   𝑥,𝐴,𝑦   𝑥,𝐵,𝑦   𝑎,𝑏,𝑥,𝑦   𝜑,𝑥,𝑦

Allowed substitution hints:   𝜑(𝑎, 𝑏)   𝐴(𝑎, 𝑏)   𝐵(𝑎, 𝑏)   𝑋(𝑥, 𝑦, 𝑎, 𝑏)

Proof of Theorem or2expropbilem1

Step	Hyp	Ref	Expression
1		vex 3458	. . . . . . . 8 ⊢ 𝑎 ∈ V
2		vex 3458	. . . . . . . 8 ⊢ 𝑏 ∈ V
3	1, 2	pm3.2i 476	. . . . . . 7 ⊢ (𝑎 ∈ V ∧ 𝑏 ∈ V)
4	3	a1i 11	. . . . . 6 ⊢ ((𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → (𝑎 ∈ V ∧ 𝑏 ∈ V))
5	4	anim1ci 628	. . . . 5 ⊢ (((𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) ∧ 𝜑) → (𝜑 ∧ (𝑎 ∈ V ∧ 𝑏 ∈ V)))
6	5	adantr 486	. . . 4 ⊢ ((((𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) ∧ 𝜑) ∧ (𝐴 = 𝑎 ∧ 𝐵 = 𝑏)) → (𝜑 ∧ (𝑎 ∈ V ∧ 𝑏 ∈ V)))
7		sbcid 3759	. . . . . . 7 ⊢ ([𝑏 / 𝑏][𝑎 / 𝑎]𝜑 ↔ [𝑎 / 𝑎]𝜑)
8		sbcid 3759	. . . . . . 7 ⊢ ([𝑎 / 𝑎]𝜑 ↔ 𝜑)
9	7, 8	sylbbr 239	. . . . . 6 ⊢ (𝜑 → [𝑏 / 𝑏][𝑎 / 𝑎]𝜑)
10	9	adantl 487	. . . . 5 ⊢ (((𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) ∧ 𝜑) → [𝑏 / 𝑏][𝑎 / 𝑎]𝜑)
11		opeq12 4845	. . . . 5 ⊢ ((𝐴 = 𝑎 ∧ 𝐵 = 𝑏) → ⟨𝐴, 𝐵⟩ = ⟨𝑎, 𝑏⟩)
12	10, 11	anim12ci 626	. . . 4 ⊢ ((((𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) ∧ 𝜑) ∧ (𝐴 = 𝑎 ∧ 𝐵 = 𝑏)) → (⟨𝐴, 𝐵⟩ = ⟨𝑎, 𝑏⟩ ∧ [𝑏 / 𝑏][𝑎 / 𝑎]𝜑))
13		nfv 1949	. . . . 5 ⊢ Ⅎ𝑥(⟨𝐴, 𝐵⟩ = ⟨𝑎, 𝑏⟩ ∧ [𝑏 / 𝑏][𝑎 / 𝑎]𝜑)
14		nfv 1949	. . . . 5 ⊢ Ⅎ𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑎, 𝑏⟩ ∧ [𝑏 / 𝑏][𝑎 / 𝑎]𝜑)
15		opeq12 4845	. . . . . . . 8 ⊢ ((𝑥 = 𝑎 ∧ 𝑦 = 𝑏) → ⟨𝑥, 𝑦⟩ = ⟨𝑎, 𝑏⟩)
16	15	eqeq2d 2774	. . . . . . 7 ⊢ ((𝑥 = 𝑎 ∧ 𝑦 = 𝑏) → (⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ↔ ⟨𝐴, 𝐵⟩ = ⟨𝑎, 𝑏⟩))
17		dfsbcq 3744	. . . . . . . 8 ⊢ (𝑦 = 𝑏 → ([𝑦 / 𝑏][𝑥 / 𝑎]𝜑 ↔ [𝑏 / 𝑏][𝑥 / 𝑎]𝜑))
18		dfsbcq 3744	. . . . . . . . 9 ⊢ (𝑥 = 𝑎 → ([𝑥 / 𝑎]𝜑 ↔ [𝑎 / 𝑎]𝜑))
19	18	sbcbidv 3797	. . . . . . . 8 ⊢ (𝑥 = 𝑎 → ([𝑏 / 𝑏][𝑥 / 𝑎]𝜑 ↔ [𝑏 / 𝑏][𝑎 / 𝑎]𝜑))
20	17, 19	sylan9bbr 520	. . . . . . 7 ⊢ ((𝑥 = 𝑎 ∧ 𝑦 = 𝑏) → ([𝑦 / 𝑏][𝑥 / 𝑎]𝜑 ↔ [𝑏 / 𝑏][𝑎 / 𝑎]𝜑))
21	16, 20	anbi12d 644	. . . . . 6 ⊢ ((𝑥 = 𝑎 ∧ 𝑦 = 𝑏) → ((⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ [𝑦 / 𝑏][𝑥 / 𝑎]𝜑) ↔ (⟨𝐴, 𝐵⟩ = ⟨𝑎, 𝑏⟩ ∧ [𝑏 / 𝑏][𝑎 / 𝑎]𝜑)))
22	21	adantl 487	. . . . 5 ⊢ ((𝜑 ∧ (𝑥 = 𝑎 ∧ 𝑦 = 𝑏)) → ((⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ [𝑦 / 𝑏][𝑥 / 𝑎]𝜑) ↔ (⟨𝐴, 𝐵⟩ = ⟨𝑎, 𝑏⟩ ∧ [𝑏 / 𝑏][𝑎 / 𝑎]𝜑)))
23	13, 14, 22	spc2ed 3559	. . . 4 ⊢ ((𝜑 ∧ (𝑎 ∈ V ∧ 𝑏 ∈ V)) → ((⟨𝐴, 𝐵⟩ = ⟨𝑎, 𝑏⟩ ∧ [𝑏 / 𝑏][𝑎 / 𝑎]𝜑) → ∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ [𝑦 / 𝑏][𝑥 / 𝑎]𝜑)))
24	6, 12, 23	sylc 66	. . 3 ⊢ ((((𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) ∧ 𝜑) ∧ (𝐴 = 𝑎 ∧ 𝐵 = 𝑏)) → ∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ [𝑦 / 𝑏][𝑥 / 𝑎]𝜑))
25	24	exp31 425	. 2 ⊢ ((𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → (𝜑 → ((𝐴 = 𝑎 ∧ 𝐵 = 𝑏) → ∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ [𝑦 / 𝑏][𝑥 / 𝑎]𝜑))))
26	25	com23 87	1 ⊢ ((𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → ((𝐴 = 𝑎 ∧ 𝐵 = 𝑏) → (𝜑 → ∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ [𝑦 / 𝑏][𝑥 / 𝑎]𝜑))))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   = wceq 1570  ∃wex 1812   ∈ wcel 2147  Vcvv 3454  [wsbc 3742  ⟨cop 4838

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1945  ax-6 2002  ax-7 2043  ax-8 2149  ax-9 2157  ax-12 2216  ax-ext 2735

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2102  df-clab 2742  df-cleq 2755  df-clel 2839  df-rab 3417  df-v 3456  df-sbc 3743  df-ss 3901  df-dif 4050  df-un 4154  df-nul 4282  df-if 4486  df-sn 4589  df-pr 4591  df-op 4839

This theorem is used by:  or2expropbi  48309  ich2exprop  48758