Theorem reuprg0 4683

Description: Convert a restricted existential uniqueness over a pair to a disjunction of conjunctions. (Contributed by AV, 2-Apr-2023.)

Hypotheses

Ref	Expression
reuprg.1	⊢ (𝑥 = 𝐴 → (𝜑 ↔ 𝜓))
reuprg.2	⊢ (𝑥 = 𝐵 → (𝜑 ↔ 𝜒))

Assertion

Ref	Expression
reuprg0	⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∃!𝑥 ∈ {𝐴, 𝐵}𝜑 ↔ ((𝜓 ∧ (𝜒 → 𝐴 = 𝐵)) ∨ (𝜒 ∧ (𝜓 → 𝐴 = 𝐵)))))

Distinct variable groups:   𝑥,𝐴   𝑥,𝐵   𝜓,𝑥   𝜒,𝑥

Allowed substitution hints:   𝜑(𝑥)   𝑉(𝑥)   𝑊(𝑥)

Proof of Theorem reuprg0

Dummy variables 𝑤 𝑐 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		nfsbc1v 3790	. . 3 ⊢ Ⅎ𝑥[𝑐 / 𝑥]𝜑
2		nfsbc1v 3790	. . 3 ⊢ Ⅎ𝑥[𝑤 / 𝑥]𝜑
3		sbceq1a 3781	. . 3 ⊢ (𝑥 = 𝑤 → (𝜑 ↔ [𝑤 / 𝑥]𝜑))
4		dfsbcq 3772	. . 3 ⊢ (𝑤 = 𝑐 → ([𝑤 / 𝑥]𝜑 ↔ [𝑐 / 𝑥]𝜑))
5	1, 2, 3, 4	reu8nf 3857	. 2 ⊢ (∃!𝑥 ∈ {𝐴, 𝐵}𝜑 ↔ ∃𝑥 ∈ {𝐴, 𝐵} (𝜑 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝑥 = 𝑐)))
6		nfv 1914	. . . . 5 ⊢ Ⅎ𝑥𝜓
7		nfcv 2899	. . . . . 6 ⊢ Ⅎ𝑥{𝐴, 𝐵}
8		nfv 1914	. . . . . . 7 ⊢ Ⅎ𝑥 𝐴 = 𝑐
9	1, 8	nfim 1896	. . . . . 6 ⊢ Ⅎ𝑥([𝑐 / 𝑥]𝜑 → 𝐴 = 𝑐)
10	7, 9	nfralw 3295	. . . . 5 ⊢ Ⅎ𝑥∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐴 = 𝑐)
11	6, 10	nfan 1899	. . . 4 ⊢ Ⅎ𝑥(𝜓 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐴 = 𝑐))
12		nfv 1914	. . . . 5 ⊢ Ⅎ𝑥𝜒
13		nfv 1914	. . . . . . 7 ⊢ Ⅎ𝑥 𝐵 = 𝑐
14	1, 13	nfim 1896	. . . . . 6 ⊢ Ⅎ𝑥([𝑐 / 𝑥]𝜑 → 𝐵 = 𝑐)
15	7, 14	nfralw 3295	. . . . 5 ⊢ Ⅎ𝑥∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐵 = 𝑐)
16	12, 15	nfan 1899	. . . 4 ⊢ Ⅎ𝑥(𝜒 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐵 = 𝑐))
17		reuprg.1	. . . . 5 ⊢ (𝑥 = 𝐴 → (𝜑 ↔ 𝜓))
18		eqeq1 2740	. . . . . . 7 ⊢ (𝑥 = 𝐴 → (𝑥 = 𝑐 ↔ 𝐴 = 𝑐))
19	18	imbi2d 340	. . . . . 6 ⊢ (𝑥 = 𝐴 → (([𝑐 / 𝑥]𝜑 → 𝑥 = 𝑐) ↔ ([𝑐 / 𝑥]𝜑 → 𝐴 = 𝑐)))
20	19	ralbidv 3164	. . . . 5 ⊢ (𝑥 = 𝐴 → (∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝑥 = 𝑐) ↔ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐴 = 𝑐)))
21	17, 20	anbi12d 632	. . . 4 ⊢ (𝑥 = 𝐴 → ((𝜑 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝑥 = 𝑐)) ↔ (𝜓 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐴 = 𝑐))))
22		reuprg.2	. . . . 5 ⊢ (𝑥 = 𝐵 → (𝜑 ↔ 𝜒))
23		eqeq1 2740	. . . . . . 7 ⊢ (𝑥 = 𝐵 → (𝑥 = 𝑐 ↔ 𝐵 = 𝑐))
24	23	imbi2d 340	. . . . . 6 ⊢ (𝑥 = 𝐵 → (([𝑐 / 𝑥]𝜑 → 𝑥 = 𝑐) ↔ ([𝑐 / 𝑥]𝜑 → 𝐵 = 𝑐)))
25	24	ralbidv 3164	. . . . 5 ⊢ (𝑥 = 𝐵 → (∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝑥 = 𝑐) ↔ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐵 = 𝑐)))
26	22, 25	anbi12d 632	. . . 4 ⊢ (𝑥 = 𝐵 → ((𝜑 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝑥 = 𝑐)) ↔ (𝜒 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐵 = 𝑐))))
27	11, 16, 21, 26	rexprgf 4676	. . 3 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∃𝑥 ∈ {𝐴, 𝐵} (𝜑 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝑥 = 𝑐)) ↔ ((𝜓 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐴 = 𝑐)) ∨ (𝜒 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐵 = 𝑐)))))
28		dfsbcq 3772	. . . . . . . 8 ⊢ (𝑐 = 𝐴 → ([𝑐 / 𝑥]𝜑 ↔ [𝐴 / 𝑥]𝜑))
29		eqeq2 2748	. . . . . . . 8 ⊢ (𝑐 = 𝐴 → (𝐴 = 𝑐 ↔ 𝐴 = 𝐴))
30	28, 29	imbi12d 344	. . . . . . 7 ⊢ (𝑐 = 𝐴 → (([𝑐 / 𝑥]𝜑 → 𝐴 = 𝑐) ↔ ([𝐴 / 𝑥]𝜑 → 𝐴 = 𝐴)))
31		dfsbcq 3772	. . . . . . . 8 ⊢ (𝑐 = 𝐵 → ([𝑐 / 𝑥]𝜑 ↔ [𝐵 / 𝑥]𝜑))
32		eqeq2 2748	. . . . . . . 8 ⊢ (𝑐 = 𝐵 → (𝐴 = 𝑐 ↔ 𝐴 = 𝐵))
33	31, 32	imbi12d 344	. . . . . . 7 ⊢ (𝑐 = 𝐵 → (([𝑐 / 𝑥]𝜑 → 𝐴 = 𝑐) ↔ ([𝐵 / 𝑥]𝜑 → 𝐴 = 𝐵)))
34	30, 33	ralprg 4677	. . . . . 6 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐴 = 𝑐) ↔ (([𝐴 / 𝑥]𝜑 → 𝐴 = 𝐴) ∧ ([𝐵 / 𝑥]𝜑 → 𝐴 = 𝐵))))
35		eqidd 2737	. . . . . . . 8 ⊢ ([𝐴 / 𝑥]𝜑 → 𝐴 = 𝐴)
36	35	biantrur 530	. . . . . . 7 ⊢ (([𝐵 / 𝑥]𝜑 → 𝐴 = 𝐵) ↔ (([𝐴 / 𝑥]𝜑 → 𝐴 = 𝐴) ∧ ([𝐵 / 𝑥]𝜑 → 𝐴 = 𝐵)))
37	22	sbcieg 3810	. . . . . . . . 9 ⊢ (𝐵 ∈ 𝑊 → ([𝐵 / 𝑥]𝜑 ↔ 𝜒))
38	37	adantl 481	. . . . . . . 8 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ([𝐵 / 𝑥]𝜑 ↔ 𝜒))
39	38	imbi1d 341	. . . . . . 7 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (([𝐵 / 𝑥]𝜑 → 𝐴 = 𝐵) ↔ (𝜒 → 𝐴 = 𝐵)))
40	36, 39	bitr3id 285	. . . . . 6 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ((([𝐴 / 𝑥]𝜑 → 𝐴 = 𝐴) ∧ ([𝐵 / 𝑥]𝜑 → 𝐴 = 𝐵)) ↔ (𝜒 → 𝐴 = 𝐵)))
41	34, 40	bitrd 279	. . . . 5 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐴 = 𝑐) ↔ (𝜒 → 𝐴 = 𝐵)))
42	41	anbi2d 630	. . . 4 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ((𝜓 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐴 = 𝑐)) ↔ (𝜓 ∧ (𝜒 → 𝐴 = 𝐵))))
43		eqeq2 2748	. . . . . . . . 9 ⊢ (𝑐 = 𝐴 → (𝐵 = 𝑐 ↔ 𝐵 = 𝐴))
44	28, 43	imbi12d 344	. . . . . . . 8 ⊢ (𝑐 = 𝐴 → (([𝑐 / 𝑥]𝜑 → 𝐵 = 𝑐) ↔ ([𝐴 / 𝑥]𝜑 → 𝐵 = 𝐴)))
45		eqeq2 2748	. . . . . . . . 9 ⊢ (𝑐 = 𝐵 → (𝐵 = 𝑐 ↔ 𝐵 = 𝐵))
46	31, 45	imbi12d 344	. . . . . . . 8 ⊢ (𝑐 = 𝐵 → (([𝑐 / 𝑥]𝜑 → 𝐵 = 𝑐) ↔ ([𝐵 / 𝑥]𝜑 → 𝐵 = 𝐵)))
47	44, 46	ralprg 4677	. . . . . . 7 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐵 = 𝑐) ↔ (([𝐴 / 𝑥]𝜑 → 𝐵 = 𝐴) ∧ ([𝐵 / 𝑥]𝜑 → 𝐵 = 𝐵))))
48		eqidd 2737	. . . . . . . . 9 ⊢ ([𝐵 / 𝑥]𝜑 → 𝐵 = 𝐵)
49	48	biantru 529	. . . . . . . 8 ⊢ (([𝐴 / 𝑥]𝜑 → 𝐵 = 𝐴) ↔ (([𝐴 / 𝑥]𝜑 → 𝐵 = 𝐴) ∧ ([𝐵 / 𝑥]𝜑 → 𝐵 = 𝐵)))
50	17	sbcieg 3810	. . . . . . . . . 10 ⊢ (𝐴 ∈ 𝑉 → ([𝐴 / 𝑥]𝜑 ↔ 𝜓))
51	50	adantr 480	. . . . . . . . 9 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ([𝐴 / 𝑥]𝜑 ↔ 𝜓))
52	51	imbi1d 341	. . . . . . . 8 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (([𝐴 / 𝑥]𝜑 → 𝐵 = 𝐴) ↔ (𝜓 → 𝐵 = 𝐴)))
53	49, 52	bitr3id 285	. . . . . . 7 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ((([𝐴 / 𝑥]𝜑 → 𝐵 = 𝐴) ∧ ([𝐵 / 𝑥]𝜑 → 𝐵 = 𝐵)) ↔ (𝜓 → 𝐵 = 𝐴)))
54	47, 53	bitrd 279	. . . . . 6 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐵 = 𝑐) ↔ (𝜓 → 𝐵 = 𝐴)))
55	54	anbi2d 630	. . . . 5 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ((𝜒 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐵 = 𝑐)) ↔ (𝜒 ∧ (𝜓 → 𝐵 = 𝐴))))
56		eqcom 2743	. . . . . . 7 ⊢ (𝐵 = 𝐴 ↔ 𝐴 = 𝐵)
57	56	imbi2i 336	. . . . . 6 ⊢ ((𝜓 → 𝐵 = 𝐴) ↔ (𝜓 → 𝐴 = 𝐵))
58	57	anbi2i 623	. . . . 5 ⊢ ((𝜒 ∧ (𝜓 → 𝐵 = 𝐴)) ↔ (𝜒 ∧ (𝜓 → 𝐴 = 𝐵)))
59	55, 58	bitrdi 287	. . . 4 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ((𝜒 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐵 = 𝑐)) ↔ (𝜒 ∧ (𝜓 → 𝐴 = 𝐵))))
60	42, 59	orbi12d 918	. . 3 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (((𝜓 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐴 = 𝑐)) ∨ (𝜒 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝐵 = 𝑐))) ↔ ((𝜓 ∧ (𝜒 → 𝐴 = 𝐵)) ∨ (𝜒 ∧ (𝜓 → 𝐴 = 𝐵)))))
61	27, 60	bitrd 279	. 2 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∃𝑥 ∈ {𝐴, 𝐵} (𝜑 ∧ ∀𝑐 ∈ {𝐴, 𝐵} ([𝑐 / 𝑥]𝜑 → 𝑥 = 𝑐)) ↔ ((𝜓 ∧ (𝜒 → 𝐴 = 𝐵)) ∨ (𝜒 ∧ (𝜓 → 𝐴 = 𝐵)))))
62	5, 61	bitrid 283	1 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∃!𝑥 ∈ {𝐴, 𝐵}𝜑 ↔ ((𝜓 ∧ (𝜒 → 𝐴 = 𝐵)) ∨ (𝜒 ∧ (𝜓 → 𝐴 = 𝐵)))))

Syntax hints:   → wi 4   ↔ wb 206   ∧ wa 395   ∨ wo 847   = wceq 1540   ∈ wcel 2109  ∀wral 3052  ∃wrex 3061  ∃!wreu 3362  [wsbc 3770  {cpr 4608

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008  ax-8 2111  ax-9 2119  ax-10 2142  ax-11 2158  ax-12 2178  ax-ext 2708

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1543  df-ex 1780  df-nf 1784  df-sb 2066  df-mo 2540  df-eu 2569  df-clab 2715  df-cleq 2728  df-clel 2810  df-nfc 2886  df-ral 3053  df-rex 3062  df-rmo 3364  df-reu 3365  df-v 3466  df-sbc 3771  df-un 3936  df-sn 4607  df-pr 4609

This theorem is referenced by:  reuprg  4684