Theorem ecopovsym 8840

Description: Assuming the operation 𝐹 is commutative, show that the relation ∼, specified by the first hypothesis, is symmetric. (Contributed by NM, 27-Aug-1995.) (Revised by Mario Carneiro, 26-Apr-2015.)

Hypotheses

Ref	Expression
ecopopr.1	⊢ ∼ = {⟨𝑥, 𝑦⟩ ∣ ((𝑥 ∈ (𝑆 × 𝑆) ∧ 𝑦 ∈ (𝑆 × 𝑆)) ∧ ∃𝑧∃𝑤∃𝑣∃𝑢((𝑥 = ⟨𝑧, 𝑤⟩ ∧ 𝑦 = ⟨𝑣, 𝑢⟩) ∧ (𝑧 + 𝑢) = (𝑤 + 𝑣)))}
ecopopr.com	⊢ (𝑥 + 𝑦) = (𝑦 + 𝑥)

Assertion

Ref	Expression
ecopovsym	⊢ (𝐴 ∼ 𝐵 → 𝐵 ∼ 𝐴)

Distinct variable groups:   𝑥,𝑦,𝑧,𝑤,𝑣,𝑢, +   𝑥,𝑆,𝑦,𝑧,𝑤,𝑣,𝑢

Allowed substitution hints:   𝐴(𝑥, 𝑦, 𝑧, 𝑤, 𝑣, 𝑢)   𝐵(𝑥, 𝑦, 𝑧, 𝑤, 𝑣, 𝑢)   ∼ (𝑥, 𝑦, 𝑧, 𝑤, 𝑣, 𝑢)

Proof of Theorem ecopovsym

Dummy variables 𝑓 𝑔 ℎ 𝑡 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		ecopopr.1	. . . . 5 ⊢ ∼ = {⟨𝑥, 𝑦⟩ ∣ ((𝑥 ∈ (𝑆 × 𝑆) ∧ 𝑦 ∈ (𝑆 × 𝑆)) ∧ ∃𝑧∃𝑤∃𝑣∃𝑢((𝑥 = ⟨𝑧, 𝑤⟩ ∧ 𝑦 = ⟨𝑣, 𝑢⟩) ∧ (𝑧 + 𝑢) = (𝑤 + 𝑣)))}
2		opabssxp 5743	. . . . 5 ⊢ {⟨𝑥, 𝑦⟩ ∣ ((𝑥 ∈ (𝑆 × 𝑆) ∧ 𝑦 ∈ (𝑆 × 𝑆)) ∧ ∃𝑧∃𝑤∃𝑣∃𝑢((𝑥 = ⟨𝑧, 𝑤⟩ ∧ 𝑦 = ⟨𝑣, 𝑢⟩) ∧ (𝑧 + 𝑢) = (𝑤 + 𝑣)))} ⊆ ((𝑆 × 𝑆) × (𝑆 × 𝑆))
3	1, 2	eqsstri 3977	. . . 4 ⊢ ∼ ⊆ ((𝑆 × 𝑆) × (𝑆 × 𝑆))
4	3	brel 5716	. . 3 ⊢ (𝐴 ∼ 𝐵 → (𝐴 ∈ (𝑆 × 𝑆) ∧ 𝐵 ∈ (𝑆 × 𝑆)))
5		eqid 2761	. . . 4 ⊢ (𝑆 × 𝑆) = (𝑆 × 𝑆)
6		breq1 5106	. . . . 5 ⊢ (⟨𝑓, 𝑔⟩ = 𝐴 → (⟨𝑓, 𝑔⟩ ∼ ⟨ℎ, 𝑡⟩ ↔ 𝐴 ∼ ⟨ℎ, 𝑡⟩))
7		breq2 5107	. . . . 5 ⊢ (⟨𝑓, 𝑔⟩ = 𝐴 → (⟨ℎ, 𝑡⟩ ∼ ⟨𝑓, 𝑔⟩ ↔ ⟨ℎ, 𝑡⟩ ∼ 𝐴))
8	6, 7	bibi12d 348	. . . 4 ⊢ (⟨𝑓, 𝑔⟩ = 𝐴 → ((⟨𝑓, 𝑔⟩ ∼ ⟨ℎ, 𝑡⟩ ↔ ⟨ℎ, 𝑡⟩ ∼ ⟨𝑓, 𝑔⟩) ↔ (𝐴 ∼ ⟨ℎ, 𝑡⟩ ↔ ⟨ℎ, 𝑡⟩ ∼ 𝐴)))
9		breq2 5107	. . . . 5 ⊢ (⟨ℎ, 𝑡⟩ = 𝐵 → (𝐴 ∼ ⟨ℎ, 𝑡⟩ ↔ 𝐴 ∼ 𝐵))
10		breq1 5106	. . . . 5 ⊢ (⟨ℎ, 𝑡⟩ = 𝐵 → (⟨ℎ, 𝑡⟩ ∼ 𝐴 ↔ 𝐵 ∼ 𝐴))
11	9, 10	bibi12d 348	. . . 4 ⊢ (⟨ℎ, 𝑡⟩ = 𝐵 → ((𝐴 ∼ ⟨ℎ, 𝑡⟩ ↔ ⟨ℎ, 𝑡⟩ ∼ 𝐴) ↔ (𝐴 ∼ 𝐵 ↔ 𝐵 ∼ 𝐴)))
12	1	ecopoveq 8839	. . . . . 6 ⊢ (((𝑓 ∈ 𝑆 ∧ 𝑔 ∈ 𝑆) ∧ (ℎ ∈ 𝑆 ∧ 𝑡 ∈ 𝑆)) → (⟨𝑓, 𝑔⟩ ∼ ⟨ℎ, 𝑡⟩ ↔ (𝑓 + 𝑡) = (𝑔 + ℎ)))
13		vex 3455	. . . . . . . . 9 ⊢ 𝑓 ∈ V
14		vex 3455	. . . . . . . . 9 ⊢ 𝑡 ∈ V
15		ecopopr.com	. . . . . . . . 9 ⊢ (𝑥 + 𝑦) = (𝑦 + 𝑥)
16	13, 14, 15	caovcom 7618	. . . . . . . 8 ⊢ (𝑓 + 𝑡) = (𝑡 + 𝑓)
17		vex 3455	. . . . . . . . 9 ⊢ 𝑔 ∈ V
18		vex 3455	. . . . . . . . 9 ⊢ ℎ ∈ V
19	17, 18, 15	caovcom 7618	. . . . . . . 8 ⊢ (𝑔 + ℎ) = (ℎ + 𝑔)
20	16, 19	eqeq12i 2779	. . . . . . 7 ⊢ ((𝑓 + 𝑡) = (𝑔 + ℎ) ↔ (𝑡 + 𝑓) = (ℎ + 𝑔))
21		eqcom 2768	. . . . . . 7 ⊢ ((𝑡 + 𝑓) = (ℎ + 𝑔) ↔ (ℎ + 𝑔) = (𝑡 + 𝑓))
22	20, 21	bitri 278	. . . . . 6 ⊢ ((𝑓 + 𝑡) = (𝑔 + ℎ) ↔ (ℎ + 𝑔) = (𝑡 + 𝑓))
23	12, 22	bitrdi 290	. . . . 5 ⊢ (((𝑓 ∈ 𝑆 ∧ 𝑔 ∈ 𝑆) ∧ (ℎ ∈ 𝑆 ∧ 𝑡 ∈ 𝑆)) → (⟨𝑓, 𝑔⟩ ∼ ⟨ℎ, 𝑡⟩ ↔ (ℎ + 𝑔) = (𝑡 + 𝑓)))
24	1	ecopoveq 8839	. . . . . 6 ⊢ (((ℎ ∈ 𝑆 ∧ 𝑡 ∈ 𝑆) ∧ (𝑓 ∈ 𝑆 ∧ 𝑔 ∈ 𝑆)) → (⟨ℎ, 𝑡⟩ ∼ ⟨𝑓, 𝑔⟩ ↔ (ℎ + 𝑔) = (𝑡 + 𝑓)))
25	24	ancoms 464	. . . . 5 ⊢ (((𝑓 ∈ 𝑆 ∧ 𝑔 ∈ 𝑆) ∧ (ℎ ∈ 𝑆 ∧ 𝑡 ∈ 𝑆)) → (⟨ℎ, 𝑡⟩ ∼ ⟨𝑓, 𝑔⟩ ↔ (ℎ + 𝑔) = (𝑡 + 𝑓)))
26	23, 25	bitr4d 285	. . . 4 ⊢ (((𝑓 ∈ 𝑆 ∧ 𝑔 ∈ 𝑆) ∧ (ℎ ∈ 𝑆 ∧ 𝑡 ∈ 𝑆)) → (⟨𝑓, 𝑔⟩ ∼ ⟨ℎ, 𝑡⟩ ↔ ⟨ℎ, 𝑡⟩ ∼ ⟨𝑓, 𝑔⟩))
27	5, 8, 11, 26	2optocl 5747	. . 3 ⊢ ((𝐴 ∈ (𝑆 × 𝑆) ∧ 𝐵 ∈ (𝑆 × 𝑆)) → (𝐴 ∼ 𝐵 ↔ 𝐵 ∼ 𝐴))
28	4, 27	syl 18	. 2 ⊢ (𝐴 ∼ 𝐵 → (𝐴 ∼ 𝐵 ↔ 𝐵 ∼ 𝐴))
29	28	ibi 270	1 ⊢ (𝐴 ∼ 𝐵 → 𝐵 ∼ 𝐴)

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   = wceq 1570  ∃wex 1812   ∈ wcel 2145  ⟨cop 4590   class class class wbr 5103  {copab 5167   × cxp 5649  (class class class)co 7420

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 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-ext 2733  ax-sep 5249  ax-pr 5391

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-sb 2100  df-clab 2740  df-cleq 2753  df-clel 2836  df-ral 3078  df-rex 3088  df-rab 3414  df-v 3453  df-dif 3902  df-un 3904  df-in 3906  df-ss 3916  df-nul 4280  df-if 4483  df-sn 4585  df-pr 4587  df-op 4591  df-uni 4868  df-br 5104  df-opab 5168  df-xp 5657  df-iota 6494  df-fv 6546  df-ov 7423

This theorem is used by:  ecopover  8842