Theorem sprsymrelfolem2 44945

Description: Lemma 2 for sprsymrelfo 44949. (Contributed by AV, 23-Nov-2021.)

Hypothesis

Ref	Expression
sprsymrelfo.q	⊢ 𝑄 = {𝑞 ∈ (Pairs‘𝑉) ∣ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑞 = {𝑎, 𝑏} → 𝑎𝑅𝑏)}

Assertion

Ref	Expression
sprsymrelfolem2	⊢ ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) → (𝑥𝑅𝑦 ↔ ∃𝑐 ∈ 𝑄 𝑐 = {𝑥, 𝑦}))

Distinct variable groups:   𝑉,𝑞   𝑄,𝑐   𝑅,𝑎,𝑏,𝑐,𝑞,𝑥,𝑦   𝑉,𝑎,𝑏,𝑐,𝑥,𝑦   𝑊,𝑎,𝑏,𝑐

Allowed substitution hints:   𝑄(𝑥,𝑦,𝑞,𝑎,𝑏)   𝑊(𝑥,𝑦,𝑞)

Proof of Theorem sprsymrelfolem2

Step	Hyp	Ref	Expression
1		df-br 5075	. . . . . . . 8 ⊢ (𝑥𝑅𝑦 ↔ ⟨𝑥, 𝑦⟩ ∈ 𝑅)
2		simpl 483	. . . . . . . . . 10 ⊢ ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉)) → 𝑉 ∈ 𝑊)
3		ssel 3914	. . . . . . . . . . . . 13 ⊢ (𝑅 ⊆ (𝑉 × 𝑉) → (⟨𝑥, 𝑦⟩ ∈ 𝑅 → ⟨𝑥, 𝑦⟩ ∈ (𝑉 × 𝑉)))
4	3	adantl 482	. . . . . . . . . . . 12 ⊢ ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉)) → (⟨𝑥, 𝑦⟩ ∈ 𝑅 → ⟨𝑥, 𝑦⟩ ∈ (𝑉 × 𝑉)))
5	4	imp 407	. . . . . . . . . . 11 ⊢ (((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉)) ∧ ⟨𝑥, 𝑦⟩ ∈ 𝑅) → ⟨𝑥, 𝑦⟩ ∈ (𝑉 × 𝑉))
6		opelxp 5625	. . . . . . . . . . 11 ⊢ (⟨𝑥, 𝑦⟩ ∈ (𝑉 × 𝑉) ↔ (𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉))
7	5, 6	sylib 217	. . . . . . . . . 10 ⊢ (((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉)) ∧ ⟨𝑥, 𝑦⟩ ∈ 𝑅) → (𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉))
8		prelspr 44938	. . . . . . . . . 10 ⊢ ((𝑉 ∈ 𝑊 ∧ (𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉)) → {𝑥, 𝑦} ∈ (Pairs‘𝑉))
9	2, 7, 8	syl2an2r 682	. . . . . . . . 9 ⊢ (((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉)) ∧ ⟨𝑥, 𝑦⟩ ∈ 𝑅) → {𝑥, 𝑦} ∈ (Pairs‘𝑉))
10	9	ex 413	. . . . . . . 8 ⊢ ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉)) → (⟨𝑥, 𝑦⟩ ∈ 𝑅 → {𝑥, 𝑦} ∈ (Pairs‘𝑉)))
11	1, 10	syl5bi 241	. . . . . . 7 ⊢ ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉)) → (𝑥𝑅𝑦 → {𝑥, 𝑦} ∈ (Pairs‘𝑉)))
12	11	3adant3 1131	. . . . . 6 ⊢ ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) → (𝑥𝑅𝑦 → {𝑥, 𝑦} ∈ (Pairs‘𝑉)))
13	12	imp 407	. . . . 5 ⊢ (((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦) → {𝑥, 𝑦} ∈ (Pairs‘𝑉))
14		vex 3436	. . . . . . . 8 ⊢ 𝑥 ∈ V
15		vex 3436	. . . . . . . 8 ⊢ 𝑦 ∈ V
16		vex 3436	. . . . . . . 8 ⊢ 𝑎 ∈ V
17		vex 3436	. . . . . . . 8 ⊢ 𝑏 ∈ V
18	14, 15, 16, 17	preq12b 4781	. . . . . . 7 ⊢ ({𝑥, 𝑦} = {𝑎, 𝑏} ↔ ((𝑥 = 𝑎 ∧ 𝑦 = 𝑏) ∨ (𝑥 = 𝑏 ∧ 𝑦 = 𝑎)))
19		breq12 5079	. . . . . . . . . . . . . 14 ⊢ ((𝑥 = 𝑎 ∧ 𝑦 = 𝑏) → (𝑥𝑅𝑦 ↔ 𝑎𝑅𝑏))
20	19	biimpd 228	. . . . . . . . . . . . 13 ⊢ ((𝑥 = 𝑎 ∧ 𝑦 = 𝑏) → (𝑥𝑅𝑦 → 𝑎𝑅𝑏))
21	20	com12 32	. . . . . . . . . . . 12 ⊢ (𝑥𝑅𝑦 → ((𝑥 = 𝑎 ∧ 𝑦 = 𝑏) → 𝑎𝑅𝑏))
22	21	adantl 482	. . . . . . . . . . 11 ⊢ (((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦) → ((𝑥 = 𝑎 ∧ 𝑦 = 𝑏) → 𝑎𝑅𝑏))
23	22	adantr 481	. . . . . . . . . 10 ⊢ ((((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦) ∧ (𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉)) → ((𝑥 = 𝑎 ∧ 𝑦 = 𝑏) → 𝑎𝑅𝑏))
24	23	com12 32	. . . . . . . . 9 ⊢ ((𝑥 = 𝑎 ∧ 𝑦 = 𝑏) → ((((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦) ∧ (𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉)) → 𝑎𝑅𝑏))
25		rsp2 3138	. . . . . . . . . . . . . . . . . . 19 ⊢ (∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥) → ((𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉) → (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)))
26	25	ancomsd 466	. . . . . . . . . . . . . . . . . 18 ⊢ (∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥) → ((𝑦 ∈ 𝑉 ∧ 𝑥 ∈ 𝑉) → (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)))
27	26	imp 407	. . . . . . . . . . . . . . . . 17 ⊢ ((∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥) ∧ (𝑦 ∈ 𝑉 ∧ 𝑥 ∈ 𝑉)) → (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥))
28	27	biimpd 228	. . . . . . . . . . . . . . . 16 ⊢ ((∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥) ∧ (𝑦 ∈ 𝑉 ∧ 𝑥 ∈ 𝑉)) → (𝑥𝑅𝑦 → 𝑦𝑅𝑥))
29	28	ex 413	. . . . . . . . . . . . . . 15 ⊢ (∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥) → ((𝑦 ∈ 𝑉 ∧ 𝑥 ∈ 𝑉) → (𝑥𝑅𝑦 → 𝑦𝑅𝑥)))
30	29	3ad2ant3 1134	. . . . . . . . . . . . . 14 ⊢ ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) → ((𝑦 ∈ 𝑉 ∧ 𝑥 ∈ 𝑉) → (𝑥𝑅𝑦 → 𝑦𝑅𝑥)))
31	30	com23 86	. . . . . . . . . . . . 13 ⊢ ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) → (𝑥𝑅𝑦 → ((𝑦 ∈ 𝑉 ∧ 𝑥 ∈ 𝑉) → 𝑦𝑅𝑥)))
32	31	imp 407	. . . . . . . . . . . 12 ⊢ (((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦) → ((𝑦 ∈ 𝑉 ∧ 𝑥 ∈ 𝑉) → 𝑦𝑅𝑥))
33	32	adantl 482	. . . . . . . . . . 11 ⊢ (((𝑥 = 𝑏 ∧ 𝑦 = 𝑎) ∧ ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦)) → ((𝑦 ∈ 𝑉 ∧ 𝑥 ∈ 𝑉) → 𝑦𝑅𝑥))
34		eleq1 2826	. . . . . . . . . . . . . 14 ⊢ (𝑦 = 𝑎 → (𝑦 ∈ 𝑉 ↔ 𝑎 ∈ 𝑉))
35		eleq1 2826	. . . . . . . . . . . . . 14 ⊢ (𝑥 = 𝑏 → (𝑥 ∈ 𝑉 ↔ 𝑏 ∈ 𝑉))
36	34, 35	bi2anan9r 637	. . . . . . . . . . . . 13 ⊢ ((𝑥 = 𝑏 ∧ 𝑦 = 𝑎) → ((𝑦 ∈ 𝑉 ∧ 𝑥 ∈ 𝑉) ↔ (𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉)))
37		breq12 5079	. . . . . . . . . . . . . 14 ⊢ ((𝑦 = 𝑎 ∧ 𝑥 = 𝑏) → (𝑦𝑅𝑥 ↔ 𝑎𝑅𝑏))
38	37	ancoms 459	. . . . . . . . . . . . 13 ⊢ ((𝑥 = 𝑏 ∧ 𝑦 = 𝑎) → (𝑦𝑅𝑥 ↔ 𝑎𝑅𝑏))
39	36, 38	imbi12d 345	. . . . . . . . . . . 12 ⊢ ((𝑥 = 𝑏 ∧ 𝑦 = 𝑎) → (((𝑦 ∈ 𝑉 ∧ 𝑥 ∈ 𝑉) → 𝑦𝑅𝑥) ↔ ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) → 𝑎𝑅𝑏)))
40	39	adantr 481	. . . . . . . . . . 11 ⊢ (((𝑥 = 𝑏 ∧ 𝑦 = 𝑎) ∧ ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦)) → (((𝑦 ∈ 𝑉 ∧ 𝑥 ∈ 𝑉) → 𝑦𝑅𝑥) ↔ ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) → 𝑎𝑅𝑏)))
41	33, 40	mpbid 231	. . . . . . . . . 10 ⊢ (((𝑥 = 𝑏 ∧ 𝑦 = 𝑎) ∧ ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦)) → ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) → 𝑎𝑅𝑏))
42	41	expimpd 454	. . . . . . . . 9 ⊢ ((𝑥 = 𝑏 ∧ 𝑦 = 𝑎) → ((((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦) ∧ (𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉)) → 𝑎𝑅𝑏))
43	24, 42	jaoi 854	. . . . . . . 8 ⊢ (((𝑥 = 𝑎 ∧ 𝑦 = 𝑏) ∨ (𝑥 = 𝑏 ∧ 𝑦 = 𝑎)) → ((((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦) ∧ (𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉)) → 𝑎𝑅𝑏))
44	43	com12 32	. . . . . . 7 ⊢ ((((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦) ∧ (𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉)) → (((𝑥 = 𝑎 ∧ 𝑦 = 𝑏) ∨ (𝑥 = 𝑏 ∧ 𝑦 = 𝑎)) → 𝑎𝑅𝑏))
45	18, 44	syl5bi 241	. . . . . 6 ⊢ ((((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦) ∧ (𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉)) → ({𝑥, 𝑦} = {𝑎, 𝑏} → 𝑎𝑅𝑏))
46	45	ralrimivva 3123	. . . . 5 ⊢ (((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦) → ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 ({𝑥, 𝑦} = {𝑎, 𝑏} → 𝑎𝑅𝑏))
47		sprsymrelfo.q	. . . . . . 7 ⊢ 𝑄 = {𝑞 ∈ (Pairs‘𝑉) ∣ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑞 = {𝑎, 𝑏} → 𝑎𝑅𝑏)}
48	47	eleq2i 2830	. . . . . 6 ⊢ ({𝑥, 𝑦} ∈ 𝑄 ↔ {𝑥, 𝑦} ∈ {𝑞 ∈ (Pairs‘𝑉) ∣ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑞 = {𝑎, 𝑏} → 𝑎𝑅𝑏)})
49		eqeq1 2742	. . . . . . . . 9 ⊢ (𝑞 = {𝑥, 𝑦} → (𝑞 = {𝑎, 𝑏} ↔ {𝑥, 𝑦} = {𝑎, 𝑏}))
50	49	imbi1d 342	. . . . . . . 8 ⊢ (𝑞 = {𝑥, 𝑦} → ((𝑞 = {𝑎, 𝑏} → 𝑎𝑅𝑏) ↔ ({𝑥, 𝑦} = {𝑎, 𝑏} → 𝑎𝑅𝑏)))
51	50	2ralbidv 3129	. . . . . . 7 ⊢ (𝑞 = {𝑥, 𝑦} → (∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑞 = {𝑎, 𝑏} → 𝑎𝑅𝑏) ↔ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 ({𝑥, 𝑦} = {𝑎, 𝑏} → 𝑎𝑅𝑏)))
52	51	elrab 3624	. . . . . 6 ⊢ ({𝑥, 𝑦} ∈ {𝑞 ∈ (Pairs‘𝑉) ∣ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑞 = {𝑎, 𝑏} → 𝑎𝑅𝑏)} ↔ ({𝑥, 𝑦} ∈ (Pairs‘𝑉) ∧ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 ({𝑥, 𝑦} = {𝑎, 𝑏} → 𝑎𝑅𝑏)))
53	48, 52	bitri 274	. . . . 5 ⊢ ({𝑥, 𝑦} ∈ 𝑄 ↔ ({𝑥, 𝑦} ∈ (Pairs‘𝑉) ∧ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 ({𝑥, 𝑦} = {𝑎, 𝑏} → 𝑎𝑅𝑏)))
54	13, 46, 53	sylanbrc 583	. . . 4 ⊢ (((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦) → {𝑥, 𝑦} ∈ 𝑄)
55		eqidd 2739	. . . 4 ⊢ (((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦) → {𝑥, 𝑦} = {𝑥, 𝑦})
56		eqeq1 2742	. . . . 5 ⊢ (𝑐 = {𝑥, 𝑦} → (𝑐 = {𝑥, 𝑦} ↔ {𝑥, 𝑦} = {𝑥, 𝑦}))
57	56	rspcev 3561	. . . 4 ⊢ (({𝑥, 𝑦} ∈ 𝑄 ∧ {𝑥, 𝑦} = {𝑥, 𝑦}) → ∃𝑐 ∈ 𝑄 𝑐 = {𝑥, 𝑦})
58	54, 55, 57	syl2anc 584	. . 3 ⊢ (((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) ∧ 𝑥𝑅𝑦) → ∃𝑐 ∈ 𝑄 𝑐 = {𝑥, 𝑦})
59	58	ex 413	. 2 ⊢ ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) → (𝑥𝑅𝑦 → ∃𝑐 ∈ 𝑄 𝑐 = {𝑥, 𝑦}))
60	47	eleq2i 2830	. . . . . 6 ⊢ (𝑐 ∈ 𝑄 ↔ 𝑐 ∈ {𝑞 ∈ (Pairs‘𝑉) ∣ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑞 = {𝑎, 𝑏} → 𝑎𝑅𝑏)})
61		eqeq1 2742	. . . . . . . . 9 ⊢ (𝑞 = 𝑐 → (𝑞 = {𝑎, 𝑏} ↔ 𝑐 = {𝑎, 𝑏}))
62	61	imbi1d 342	. . . . . . . 8 ⊢ (𝑞 = 𝑐 → ((𝑞 = {𝑎, 𝑏} → 𝑎𝑅𝑏) ↔ (𝑐 = {𝑎, 𝑏} → 𝑎𝑅𝑏)))
63	62	2ralbidv 3129	. . . . . . 7 ⊢ (𝑞 = 𝑐 → (∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑞 = {𝑎, 𝑏} → 𝑎𝑅𝑏) ↔ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑐 = {𝑎, 𝑏} → 𝑎𝑅𝑏)))
64	63	elrab 3624	. . . . . 6 ⊢ (𝑐 ∈ {𝑞 ∈ (Pairs‘𝑉) ∣ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑞 = {𝑎, 𝑏} → 𝑎𝑅𝑏)} ↔ (𝑐 ∈ (Pairs‘𝑉) ∧ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑐 = {𝑎, 𝑏} → 𝑎𝑅𝑏)))
65	60, 64	bitri 274	. . . . 5 ⊢ (𝑐 ∈ 𝑄 ↔ (𝑐 ∈ (Pairs‘𝑉) ∧ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑐 = {𝑎, 𝑏} → 𝑎𝑅𝑏)))
66		eleq1 2826	. . . . . . . . . . 11 ⊢ (𝑐 = {𝑥, 𝑦} → (𝑐 ∈ (Pairs‘𝑉) ↔ {𝑥, 𝑦} ∈ (Pairs‘𝑉)))
67		prsprel 44939	. . . . . . . . . . . 12 ⊢ (({𝑥, 𝑦} ∈ (Pairs‘𝑉) ∧ (𝑥 ∈ V ∧ 𝑦 ∈ V)) → (𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉))
68	14, 15, 67	mpanr12 702	. . . . . . . . . . 11 ⊢ ({𝑥, 𝑦} ∈ (Pairs‘𝑉) → (𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉))
69	66, 68	syl6bi 252	. . . . . . . . . 10 ⊢ (𝑐 = {𝑥, 𝑦} → (𝑐 ∈ (Pairs‘𝑉) → (𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉)))
70	69	com12 32	. . . . . . . . 9 ⊢ (𝑐 ∈ (Pairs‘𝑉) → (𝑐 = {𝑥, 𝑦} → (𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉)))
71	70	adantr 481	. . . . . . . 8 ⊢ ((𝑐 ∈ (Pairs‘𝑉) ∧ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑐 = {𝑎, 𝑏} → 𝑎𝑅𝑏)) → (𝑐 = {𝑥, 𝑦} → (𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉)))
72	71	imp 407	. . . . . . 7 ⊢ (((𝑐 ∈ (Pairs‘𝑉) ∧ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑐 = {𝑎, 𝑏} → 𝑎𝑅𝑏)) ∧ 𝑐 = {𝑥, 𝑦}) → (𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉))
73		preq1 4669	. . . . . . . . . . . 12 ⊢ (𝑎 = 𝑥 → {𝑎, 𝑏} = {𝑥, 𝑏})
74	73	eqeq2d 2749	. . . . . . . . . . 11 ⊢ (𝑎 = 𝑥 → (𝑐 = {𝑎, 𝑏} ↔ 𝑐 = {𝑥, 𝑏}))
75		breq1 5077	. . . . . . . . . . 11 ⊢ (𝑎 = 𝑥 → (𝑎𝑅𝑏 ↔ 𝑥𝑅𝑏))
76	74, 75	imbi12d 345	. . . . . . . . . 10 ⊢ (𝑎 = 𝑥 → ((𝑐 = {𝑎, 𝑏} → 𝑎𝑅𝑏) ↔ (𝑐 = {𝑥, 𝑏} → 𝑥𝑅𝑏)))
77		preq2 4670	. . . . . . . . . . . 12 ⊢ (𝑏 = 𝑦 → {𝑥, 𝑏} = {𝑥, 𝑦})
78	77	eqeq2d 2749	. . . . . . . . . . 11 ⊢ (𝑏 = 𝑦 → (𝑐 = {𝑥, 𝑏} ↔ 𝑐 = {𝑥, 𝑦}))
79		breq2 5078	. . . . . . . . . . 11 ⊢ (𝑏 = 𝑦 → (𝑥𝑅𝑏 ↔ 𝑥𝑅𝑦))
80	78, 79	imbi12d 345	. . . . . . . . . 10 ⊢ (𝑏 = 𝑦 → ((𝑐 = {𝑥, 𝑏} → 𝑥𝑅𝑏) ↔ (𝑐 = {𝑥, 𝑦} → 𝑥𝑅𝑦)))
81	76, 80	rspc2v 3570	. . . . . . . . 9 ⊢ ((𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉) → (∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑐 = {𝑎, 𝑏} → 𝑎𝑅𝑏) → (𝑐 = {𝑥, 𝑦} → 𝑥𝑅𝑦)))
82	81	a1d 25	. . . . . . . 8 ⊢ ((𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉) → (𝑐 ∈ (Pairs‘𝑉) → (∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑐 = {𝑎, 𝑏} → 𝑎𝑅𝑏) → (𝑐 = {𝑥, 𝑦} → 𝑥𝑅𝑦))))
83	82	imp4c 424	. . . . . . 7 ⊢ ((𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉) → (((𝑐 ∈ (Pairs‘𝑉) ∧ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑐 = {𝑎, 𝑏} → 𝑎𝑅𝑏)) ∧ 𝑐 = {𝑥, 𝑦}) → 𝑥𝑅𝑦))
84	72, 83	mpcom 38	. . . . . 6 ⊢ (((𝑐 ∈ (Pairs‘𝑉) ∧ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑐 = {𝑎, 𝑏} → 𝑎𝑅𝑏)) ∧ 𝑐 = {𝑥, 𝑦}) → 𝑥𝑅𝑦)
85	84	a1d 25	. . . . 5 ⊢ (((𝑐 ∈ (Pairs‘𝑉) ∧ ∀𝑎 ∈ 𝑉 ∀𝑏 ∈ 𝑉 (𝑐 = {𝑎, 𝑏} → 𝑎𝑅𝑏)) ∧ 𝑐 = {𝑥, 𝑦}) → ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) → 𝑥𝑅𝑦))
86	65, 85	sylanb 581	. . . 4 ⊢ ((𝑐 ∈ 𝑄 ∧ 𝑐 = {𝑥, 𝑦}) → ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) → 𝑥𝑅𝑦))
87	86	rexlimiva 3210	. . 3 ⊢ (∃𝑐 ∈ 𝑄 𝑐 = {𝑥, 𝑦} → ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) → 𝑥𝑅𝑦))
88	87	com12 32	. 2 ⊢ ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) → (∃𝑐 ∈ 𝑄 𝑐 = {𝑥, 𝑦} → 𝑥𝑅𝑦))
89	59, 88	impbid 211	1 ⊢ ((𝑉 ∈ 𝑊 ∧ 𝑅 ⊆ (𝑉 × 𝑉) ∧ ∀𝑥 ∈ 𝑉 ∀𝑦 ∈ 𝑉 (𝑥𝑅𝑦 ↔ 𝑦𝑅𝑥)) → (𝑥𝑅𝑦 ↔ ∃𝑐 ∈ 𝑄 𝑐 = {𝑥, 𝑦}))

Syntax hints:   → wi 4   ↔ wb 205   ∧ wa 396   ∨ wo 844   ∧ w3a 1086   = wceq 1539   ∈ wcel 2106  ∀wral 3064  ∃wrex 3065  {crab 3068  Vcvv 3432   ⊆ wss 3887  {cpr 4563  ⟨cop 4567   class class class wbr 5074   × cxp 5587  ‘cfv 6433  Pairscspr 44929

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1798  ax-4 1812  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-10 2137  ax-11 2154  ax-12 2171  ax-ext 2709  ax-rep 5209  ax-sep 5223  ax-nul 5230  ax-pr 5352  ax-un 7588

This theorem depends on definitions:  df-bi 206  df-an 397  df-or 845  df-3an 1088  df-tru 1542  df-fal 1552  df-ex 1783  df-nf 1787  df-sb 2068  df-mo 2540  df-eu 2569  df-clab 2716  df-cleq 2730  df-clel 2816  df-nfc 2889  df-ral 3069  df-rex 3070  df-rab 3073  df-v 3434  df-sbc 3717  df-csb 3833  df-dif 3890  df-un 3892  df-in 3894  df-ss 3904  df-nul 4257  df-if 4460  df-pw 4535  df-sn 4562  df-pr 4564  df-op 4568  df-uni 4840  df-iun 4926  df-br 5075  df-opab 5137  df-mpt 5158  df-id 5489  df-xp 5595  df-rel 5596  df-cnv 5597  df-co 5598  df-dm 5599  df-iota 6391  df-fun 6435  df-fv 6441  df-spr 44930

This theorem is referenced by:  sprsymrelfo  44949