Theorem euotd 3991

Description: Prove existential uniqueness for an ordered triple. (Contributed by Mario Carneiro, 20-May-2015.)

Hypotheses

Ref	Expression
euotd.1	⊢ (𝜑 → 𝐴 ∈ V)
euotd.2	⊢ (𝜑 → 𝐵 ∈ V)
euotd.3	⊢ (𝜑 → 𝐶 ∈ V)
euotd.4	⊢ (𝜑 → (𝜓 ↔ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)))

Assertion

Ref	Expression
euotd	⊢ (𝜑 → ∃!𝑥∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))

Distinct variable groups:   𝑎,𝑏,𝑐,𝑥,𝐴   𝐵,𝑎,𝑏,𝑐,𝑥   𝐶,𝑎,𝑏,𝑐,𝑥   𝜑,𝑎,𝑏,𝑐,𝑥

Allowed substitution hints:   𝜓(𝑥,𝑎,𝑏,𝑐)

Proof of Theorem euotd

Dummy variable 𝑦 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		euotd.1	. . . 4 ⊢ (𝜑 → 𝐴 ∈ V)
2		euotd.2	. . . 4 ⊢ (𝜑 → 𝐵 ∈ V)
3		euotd.3	. . . 4 ⊢ (𝜑 → 𝐶 ∈ V)
4		otexg 3967	. . . 4 ⊢ ((𝐴 ∈ V ∧ 𝐵 ∈ V ∧ 𝐶 ∈ V) → ⟨𝐴, 𝐵, 𝐶⟩ ∈ V)
5	1, 2, 3, 4	syl3anc 1135	. . 3 ⊢ (𝜑 → ⟨𝐴, 𝐵, 𝐶⟩ ∈ V)
6		euotd.4	. . . . . . . . . . . . 13 ⊢ (𝜑 → (𝜓 ↔ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)))
7	6	biimpa 280	. . . . . . . . . . . 12 ⊢ ((𝜑 ∧ 𝜓) → (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶))
8		vex 2560	. . . . . . . . . . . . 13 ⊢ 𝑎 ∈ V
9		vex 2560	. . . . . . . . . . . . 13 ⊢ 𝑏 ∈ V
10		vex 2560	. . . . . . . . . . . . 13 ⊢ 𝑐 ∈ V
11	8, 9, 10	otth 3979	. . . . . . . . . . . 12 ⊢ (⟨𝑎, 𝑏, 𝑐⟩ = ⟨𝐴, 𝐵, 𝐶⟩ ↔ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶))
12	7, 11	sylibr 137	. . . . . . . . . . 11 ⊢ ((𝜑 ∧ 𝜓) → ⟨𝑎, 𝑏, 𝑐⟩ = ⟨𝐴, 𝐵, 𝐶⟩)
13	12	eqeq2d 2051	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝜓) → (𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ↔ 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
14	13	biimpd 132	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝜓) → (𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ → 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
15	14	impancom 247	. . . . . . . 8 ⊢ ((𝜑 ∧ 𝑥 = ⟨𝑎, 𝑏, 𝑐⟩) → (𝜓 → 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
16	15	expimpd 345	. . . . . . 7 ⊢ (𝜑 → ((𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) → 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
17	16	exlimdv 1700	. . . . . 6 ⊢ (𝜑 → (∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) → 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
18	17	exlimdvv 1777	. . . . 5 ⊢ (𝜑 → (∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) → 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
19		tru 1247	. . . . . . . . . . 11 ⊢ ⊤
20	2	adantr 261	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ 𝑎 = 𝐴) → 𝐵 ∈ V)
21	3	ad2antrr 457	. . . . . . . . . . . . . 14 ⊢ (((𝜑 ∧ 𝑎 = 𝐴) ∧ 𝑏 = 𝐵) → 𝐶 ∈ V)
22		simpr 103	. . . . . . . . . . . . . . . . . . 19 ⊢ ((𝜑 ∧ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)) → (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶))
23	22, 11	sylibr 137	. . . . . . . . . . . . . . . . . 18 ⊢ ((𝜑 ∧ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)) → ⟨𝑎, 𝑏, 𝑐⟩ = ⟨𝐴, 𝐵, 𝐶⟩)
24	23	eqcomd 2045	. . . . . . . . . . . . . . . . 17 ⊢ ((𝜑 ∧ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)) → ⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩)
25	6	biimpar 281	. . . . . . . . . . . . . . . . 17 ⊢ ((𝜑 ∧ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)) → 𝜓)
26	24, 25	jca 290	. . . . . . . . . . . . . . . 16 ⊢ ((𝜑 ∧ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)) → (⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))
27		a1tru 1259	. . . . . . . . . . . . . . . 16 ⊢ ((𝜑 ∧ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)) → ⊤)
28	26, 27	2thd 164	. . . . . . . . . . . . . . 15 ⊢ ((𝜑 ∧ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)) → ((⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ ⊤))
29	28	3anassrs 1126	. . . . . . . . . . . . . 14 ⊢ ((((𝜑 ∧ 𝑎 = 𝐴) ∧ 𝑏 = 𝐵) ∧ 𝑐 = 𝐶) → ((⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ ⊤))
30	21, 29	sbcied 2799	. . . . . . . . . . . . 13 ⊢ (((𝜑 ∧ 𝑎 = 𝐴) ∧ 𝑏 = 𝐵) → ([𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ ⊤))
31	20, 30	sbcied 2799	. . . . . . . . . . . 12 ⊢ ((𝜑 ∧ 𝑎 = 𝐴) → ([𝐵 / 𝑏][𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ ⊤))
32	1, 31	sbcied 2799	. . . . . . . . . . 11 ⊢ (𝜑 → ([𝐴 / 𝑎][𝐵 / 𝑏][𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ ⊤))
33	19, 32	mpbiri 157	. . . . . . . . . 10 ⊢ (𝜑 → [𝐴 / 𝑎][𝐵 / 𝑏][𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))
34	33	spesbcd 2844	. . . . . . . . 9 ⊢ (𝜑 → ∃𝑎[𝐵 / 𝑏][𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))
35		nfcv 2178	. . . . . . . . . 10 ⊢ Ⅎ𝑏𝐵
36		nfsbc1v 2782	. . . . . . . . . . 11 ⊢ Ⅎ𝑏[𝐵 / 𝑏][𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)
37	36	nfex 1528	. . . . . . . . . 10 ⊢ Ⅎ𝑏∃𝑎[𝐵 / 𝑏][𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)
38		sbceq1a 2773	. . . . . . . . . . 11 ⊢ (𝑏 = 𝐵 → ([𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ [𝐵 / 𝑏][𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)))
39	38	exbidv 1706	. . . . . . . . . 10 ⊢ (𝑏 = 𝐵 → (∃𝑎[𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ ∃𝑎[𝐵 / 𝑏][𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)))
40	35, 37, 39	spcegf 2636	. . . . . . . . 9 ⊢ (𝐵 ∈ V → (∃𝑎[𝐵 / 𝑏][𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) → ∃𝑏∃𝑎[𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)))
41	2, 34, 40	sylc 56	. . . . . . . 8 ⊢ (𝜑 → ∃𝑏∃𝑎[𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))
42		nfcv 2178	. . . . . . . . 9 ⊢ Ⅎ𝑐𝐶
43		nfsbc1v 2782	. . . . . . . . . . 11 ⊢ Ⅎ𝑐[𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)
44	43	nfex 1528	. . . . . . . . . 10 ⊢ Ⅎ𝑐∃𝑎[𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)
45	44	nfex 1528	. . . . . . . . 9 ⊢ Ⅎ𝑐∃𝑏∃𝑎[𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)
46		sbceq1a 2773	. . . . . . . . . 10 ⊢ (𝑐 = 𝐶 → ((⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ [𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)))
47	46	2exbidv 1748	. . . . . . . . 9 ⊢ (𝑐 = 𝐶 → (∃𝑏∃𝑎(⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ ∃𝑏∃𝑎[𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)))
48	42, 45, 47	spcegf 2636	. . . . . . . 8 ⊢ (𝐶 ∈ V → (∃𝑏∃𝑎[𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) → ∃𝑐∃𝑏∃𝑎(⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)))
49	3, 41, 48	sylc 56	. . . . . . 7 ⊢ (𝜑 → ∃𝑐∃𝑏∃𝑎(⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))
50		excom13 1579	. . . . . . 7 ⊢ (∃𝑐∃𝑏∃𝑎(⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ ∃𝑎∃𝑏∃𝑐(⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))
51	49, 50	sylib 127	. . . . . 6 ⊢ (𝜑 → ∃𝑎∃𝑏∃𝑐(⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))
52		eqeq1 2046	. . . . . . . 8 ⊢ (𝑥 = ⟨𝐴, 𝐵, 𝐶⟩ → (𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ↔ ⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩))
53	52	anbi1d 438	. . . . . . 7 ⊢ (𝑥 = ⟨𝐴, 𝐵, 𝐶⟩ → ((𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ (⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)))
54	53	3exbidv 1749	. . . . . 6 ⊢ (𝑥 = ⟨𝐴, 𝐵, 𝐶⟩ → (∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ ∃𝑎∃𝑏∃𝑐(⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)))
55	51, 54	syl5ibrcom 146	. . . . 5 ⊢ (𝜑 → (𝑥 = ⟨𝐴, 𝐵, 𝐶⟩ → ∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)))
56	18, 55	impbid 120	. . . 4 ⊢ (𝜑 → (∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
57	56	alrimiv 1754	. . 3 ⊢ (𝜑 → ∀𝑥(∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
58		eqeq2 2049	. . . . . 6 ⊢ (𝑦 = ⟨𝐴, 𝐵, 𝐶⟩ → (𝑥 = 𝑦 ↔ 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
59	58	bibi2d 221	. . . . 5 ⊢ (𝑦 = ⟨𝐴, 𝐵, 𝐶⟩ → ((∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ 𝑥 = 𝑦) ↔ (∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩)))
60	59	albidv 1705	. . . 4 ⊢ (𝑦 = ⟨𝐴, 𝐵, 𝐶⟩ → (∀𝑥(∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ 𝑥 = 𝑦) ↔ ∀𝑥(∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩)))
61	60	spcegv 2641	. . 3 ⊢ (⟨𝐴, 𝐵, 𝐶⟩ ∈ V → (∀𝑥(∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩) → ∃𝑦∀𝑥(∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ 𝑥 = 𝑦)))
62	5, 57, 61	sylc 56	. 2 ⊢ (𝜑 → ∃𝑦∀𝑥(∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ 𝑥 = 𝑦))
63		df-eu 1903	. 2 ⊢ (∃!𝑥∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ ∃𝑦∀𝑥(∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ 𝑥 = 𝑦))
64	62, 63	sylibr 137	1 ⊢ (𝜑 → ∃!𝑥∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))

Syntax hints:   → wi 4   ∧ wa 97   ↔ wb 98   ∧ w3a 885  ∀wal 1241   = wceq 1243  ⊤wtru 1244  ∃wex 1381   ∈ wcel 1393  ∃!weu 1900  Vcvv 2557  [wsbc 2764  ⟨cotp 3379

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-io 630  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-10 1396  ax-11 1397  ax-i12 1398  ax-bndl 1399  ax-4 1400  ax-14 1405  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428  ax-ext 2022  ax-sep 3875  ax-pow 3927  ax-pr 3944

This theorem depends on definitions:  df-bi 110  df-3an 887  df-tru 1246  df-nf 1350  df-sb 1646  df-eu 1903  df-clab 2027  df-cleq 2033  df-clel 2036  df-nfc 2167  df-rex 2312  df-v 2559  df-sbc 2765  df-un 2922  df-in 2924  df-ss 2931  df-pw 3361  df-sn 3381  df-pr 3382  df-op 3384  df-ot 3385

This theorem is referenced by: (None)