Theorem euotd 4009

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 3985	. . . 4 ⊢ ((𝐴 ∈ V ∧ 𝐵 ∈ V ∧ 𝐶 ∈ V) → ⟨𝐴, 𝐵, 𝐶⟩ ∈ V)
5	1, 2, 3, 4	syl3anc 1169	. . 3 ⊢ (𝜑 → ⟨𝐴, 𝐵, 𝐶⟩ ∈ V)
6		euotd.4	. . . . . . . . . . . . 13 ⊢ (𝜑 → (𝜓 ↔ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)))
7	6	biimpa 290	. . . . . . . . . . . 12 ⊢ ((𝜑 ∧ 𝜓) → (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶))
8		vex 2604	. . . . . . . . . . . . 13 ⊢ 𝑎 ∈ V
9		vex 2604	. . . . . . . . . . . . 13 ⊢ 𝑏 ∈ V
10		vex 2604	. . . . . . . . . . . . 13 ⊢ 𝑐 ∈ V
11	8, 9, 10	otth 3997	. . . . . . . . . . . 12 ⊢ (⟨𝑎, 𝑏, 𝑐⟩ = ⟨𝐴, 𝐵, 𝐶⟩ ↔ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶))
12	7, 11	sylibr 132	. . . . . . . . . . 11 ⊢ ((𝜑 ∧ 𝜓) → ⟨𝑎, 𝑏, 𝑐⟩ = ⟨𝐴, 𝐵, 𝐶⟩)
13	12	eqeq2d 2092	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝜓) → (𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ↔ 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
14	13	biimpd 142	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝜓) → (𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ → 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
15	14	impancom 256	. . . . . . . 8 ⊢ ((𝜑 ∧ 𝑥 = ⟨𝑎, 𝑏, 𝑐⟩) → (𝜓 → 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
16	15	expimpd 355	. . . . . . 7 ⊢ (𝜑 → ((𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) → 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
17	16	exlimdv 1740	. . . . . 6 ⊢ (𝜑 → (∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) → 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
18	17	exlimdvv 1818	. . . . 5 ⊢ (𝜑 → (∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) → 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
19		tru 1288	. . . . . . . . . . 11 ⊢ ⊤
20	2	adantr 270	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ 𝑎 = 𝐴) → 𝐵 ∈ V)
21	3	ad2antrr 471	. . . . . . . . . . . . . 14 ⊢ (((𝜑 ∧ 𝑎 = 𝐴) ∧ 𝑏 = 𝐵) → 𝐶 ∈ V)
22		simpr 108	. . . . . . . . . . . . . . . . . . 19 ⊢ ((𝜑 ∧ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)) → (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶))
23	22, 11	sylibr 132	. . . . . . . . . . . . . . . . . 18 ⊢ ((𝜑 ∧ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)) → ⟨𝑎, 𝑏, 𝑐⟩ = ⟨𝐴, 𝐵, 𝐶⟩)
24	23	eqcomd 2086	. . . . . . . . . . . . . . . . 17 ⊢ ((𝜑 ∧ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)) → ⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩)
25	6	biimpar 291	. . . . . . . . . . . . . . . . 17 ⊢ ((𝜑 ∧ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)) → 𝜓)
26	24, 25	jca 300	. . . . . . . . . . . . . . . 16 ⊢ ((𝜑 ∧ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)) → (⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))
27		a1tru 1300	. . . . . . . . . . . . . . . 16 ⊢ ((𝜑 ∧ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)) → ⊤)
28	26, 27	2thd 173	. . . . . . . . . . . . . . 15 ⊢ ((𝜑 ∧ (𝑎 = 𝐴 ∧ 𝑏 = 𝐵 ∧ 𝑐 = 𝐶)) → ((⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ ⊤))
29	28	3anassrs 1160	. . . . . . . . . . . . . 14 ⊢ ((((𝜑 ∧ 𝑎 = 𝐴) ∧ 𝑏 = 𝐵) ∧ 𝑐 = 𝐶) → ((⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ ⊤))
30	21, 29	sbcied 2850	. . . . . . . . . . . . 13 ⊢ (((𝜑 ∧ 𝑎 = 𝐴) ∧ 𝑏 = 𝐵) → ([𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ ⊤))
31	20, 30	sbcied 2850	. . . . . . . . . . . 12 ⊢ ((𝜑 ∧ 𝑎 = 𝐴) → ([𝐵 / 𝑏][𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ ⊤))
32	1, 31	sbcied 2850	. . . . . . . . . . 11 ⊢ (𝜑 → ([𝐴 / 𝑎][𝐵 / 𝑏][𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ ⊤))
33	19, 32	mpbiri 166	. . . . . . . . . 10 ⊢ (𝜑 → [𝐴 / 𝑎][𝐵 / 𝑏][𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))
34	33	spesbcd 2900	. . . . . . . . 9 ⊢ (𝜑 → ∃𝑎[𝐵 / 𝑏][𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))
35		nfcv 2219	. . . . . . . . . 10 ⊢ Ⅎ𝑏𝐵
36		nfsbc1v 2833	. . . . . . . . . . 11 ⊢ Ⅎ𝑏[𝐵 / 𝑏][𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)
37	36	nfex 1568	. . . . . . . . . 10 ⊢ Ⅎ𝑏∃𝑎[𝐵 / 𝑏][𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)
38		sbceq1a 2824	. . . . . . . . . . 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 1746	. . . . . . . . . 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 2681	. . . . . . . . 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 61	. . . . . . . 8 ⊢ (𝜑 → ∃𝑏∃𝑎[𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))
42		nfcv 2219	. . . . . . . . 9 ⊢ Ⅎ𝑐𝐶
43		nfsbc1v 2833	. . . . . . . . . . 11 ⊢ Ⅎ𝑐[𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)
44	43	nfex 1568	. . . . . . . . . 10 ⊢ Ⅎ𝑐∃𝑎[𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)
45	44	nfex 1568	. . . . . . . . 9 ⊢ Ⅎ𝑐∃𝑏∃𝑎[𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)
46		sbceq1a 2824	. . . . . . . . . 10 ⊢ (𝑐 = 𝐶 → ((⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ [𝐶 / 𝑐](⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)))
47	46	2exbidv 1789	. . . . . . . . 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 2681	. . . . . . . 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 61	. . . . . . 7 ⊢ (𝜑 → ∃𝑐∃𝑏∃𝑎(⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))
50		excom13 1619	. . . . . . 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 120	. . . . . 6 ⊢ (𝜑 → ∃𝑎∃𝑏∃𝑐(⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))
52		eqeq1 2087	. . . . . . . 8 ⊢ (𝑥 = ⟨𝐴, 𝐵, 𝐶⟩ → (𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ↔ ⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩))
53	52	anbi1d 452	. . . . . . 7 ⊢ (𝑥 = ⟨𝐴, 𝐵, 𝐶⟩ → ((𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ (⟨𝐴, 𝐵, 𝐶⟩ = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)))
54	53	3exbidv 1790	. . . . . 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 155	. . . . 5 ⊢ (𝜑 → (𝑥 = ⟨𝐴, 𝐵, 𝐶⟩ → ∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓)))
56	18, 55	impbid 127	. . . 4 ⊢ (𝜑 → (∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
57	56	alrimiv 1795	. . 3 ⊢ (𝜑 → ∀𝑥(∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
58		eqeq2 2090	. . . . . 6 ⊢ (𝑦 = ⟨𝐴, 𝐵, 𝐶⟩ → (𝑥 = 𝑦 ↔ 𝑥 = ⟨𝐴, 𝐵, 𝐶⟩))
59	58	bibi2d 230	. . . . 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 1745	. . . 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 2686	. . 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 61	. 2 ⊢ (𝜑 → ∃𝑦∀𝑥(∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓) ↔ 𝑥 = 𝑦))
63		df-eu 1944	. 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 132	1 ⊢ (𝜑 → ∃!𝑥∃𝑎∃𝑏∃𝑐(𝑥 = ⟨𝑎, 𝑏, 𝑐⟩ ∧ 𝜓))

Syntax hints:   → wi 4   ∧ wa 102   ↔ wb 103   ∧ w3a 919  ∀wal 1282   = wceq 1284  ⊤wtru 1285  ∃wex 1421   ∈ wcel 1433  ∃!weu 1941  Vcvv 2601  [wsbc 2815  ⟨cotp 3402

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-io 662  ax-5 1376  ax-7 1377  ax-gen 1378  ax-ie1 1422  ax-ie2 1423  ax-8 1435  ax-10 1436  ax-11 1437  ax-i12 1438  ax-bndl 1439  ax-4 1440  ax-14 1445  ax-17 1459  ax-i9 1463  ax-ial 1467  ax-i5r 1468  ax-ext 2063  ax-sep 3896  ax-pow 3948  ax-pr 3964

This theorem depends on definitions:  df-bi 115  df-3an 921  df-tru 1287  df-nf 1390  df-sb 1686  df-eu 1944  df-clab 2068  df-cleq 2074  df-clel 2077  df-nfc 2208  df-rex 2354  df-v 2603  df-sbc 2816  df-un 2977  df-in 2979  df-ss 2986  df-pw 3384  df-sn 3404  df-pr 3405  df-op 3407  df-ot 3408

This theorem is referenced by: (None)