Theorem disjiund 5102

Description: Conditions for a collection of index unions of sets 𝐴(𝑎, 𝑏) for 𝑎 ∈ 𝑉 and 𝑏 ∈ 𝑊 to be disjoint. (Contributed by AV, 9-Jan-2022.)

Hypotheses

Ref	Expression
disjiund.1	⊢ (𝑎 = 𝑐 → 𝐴 = 𝐶)
disjiund.2	⊢ (𝑏 = 𝑑 → 𝐶 = 𝐷)
disjiund.3	⊢ (𝑎 = 𝑐 → 𝑊 = 𝑋)
disjiund.4	⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐷) → 𝑎 = 𝑐)

Assertion

Ref	Expression
disjiund	⊢ (𝜑 → Disj 𝑎 ∈ 𝑉 ∪ 𝑏 ∈ 𝑊 𝐴)

Distinct variable groups:   𝐴,𝑐,𝑑,𝑥   𝐶,𝑎,𝑑,𝑥   𝐷,𝑏   𝑉,𝑎,𝑐   𝑊,𝑏,𝑐,𝑑,𝑥   𝑋,𝑎,𝑏,𝑑,𝑥   𝜑,𝑎,𝑏,𝑐,𝑑,𝑥

Allowed substitution hints:   𝐴(𝑎, 𝑏)   𝐶(𝑏, 𝑐)   𝐷(𝑥, 𝑎, 𝑐, 𝑑)   𝑉(𝑥, 𝑏, 𝑑)   𝑊(𝑎)   𝑋(𝑐)

Proof of Theorem disjiund

Step	Hyp	Ref	Expression
1		eliun 4962	. . . . . . . . 9 ⊢ (𝑥 ∈ ∪ 𝑏 ∈ 𝑊 𝐴 ↔ ∃𝑏 ∈ 𝑊 𝑥 ∈ 𝐴)
2		eliun 4962	. . . . . . . . . . . 12 ⊢ (𝑥 ∈ ∪ 𝑏 ∈ 𝑋 𝐶 ↔ ∃𝑏 ∈ 𝑋 𝑥 ∈ 𝐶)
3		disjiund.2	. . . . . . . . . . . . . . 15 ⊢ (𝑏 = 𝑑 → 𝐶 = 𝐷)
4	3	eleq2d 2851	. . . . . . . . . . . . . 14 ⊢ (𝑏 = 𝑑 → (𝑥 ∈ 𝐶 ↔ 𝑥 ∈ 𝐷))
5	4	cbvrexvw 3246	. . . . . . . . . . . . 13 ⊢ (∃𝑏 ∈ 𝑋 𝑥 ∈ 𝐶 ↔ ∃𝑑 ∈ 𝑋 𝑥 ∈ 𝐷)
6		disjiund.4	. . . . . . . . . . . . . . . . 17 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐷) → 𝑎 = 𝑐)
7	6	3exp 1137	. . . . . . . . . . . . . . . 16 ⊢ (𝜑 → (𝑥 ∈ 𝐴 → (𝑥 ∈ 𝐷 → 𝑎 = 𝑐)))
8	7	rexlimdvw 3173	. . . . . . . . . . . . . . 15 ⊢ (𝜑 → (∃𝑏 ∈ 𝑊 𝑥 ∈ 𝐴 → (𝑥 ∈ 𝐷 → 𝑎 = 𝑐)))
9	8	imp 412	. . . . . . . . . . . . . 14 ⊢ ((𝜑 ∧ ∃𝑏 ∈ 𝑊 𝑥 ∈ 𝐴) → (𝑥 ∈ 𝐷 → 𝑎 = 𝑐))
10	9	rexlimdvw 3173	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ ∃𝑏 ∈ 𝑊 𝑥 ∈ 𝐴) → (∃𝑑 ∈ 𝑋 𝑥 ∈ 𝐷 → 𝑎 = 𝑐))
11	5, 10	biimtrid 245	. . . . . . . . . . . 12 ⊢ ((𝜑 ∧ ∃𝑏 ∈ 𝑊 𝑥 ∈ 𝐴) → (∃𝑏 ∈ 𝑋 𝑥 ∈ 𝐶 → 𝑎 = 𝑐))
12	2, 11	biimtrid 245	. . . . . . . . . . 11 ⊢ ((𝜑 ∧ ∃𝑏 ∈ 𝑊 𝑥 ∈ 𝐴) → (𝑥 ∈ ∪ 𝑏 ∈ 𝑋 𝐶 → 𝑎 = 𝑐))
13	12	con3d 153	. . . . . . . . . 10 ⊢ ((𝜑 ∧ ∃𝑏 ∈ 𝑊 𝑥 ∈ 𝐴) → (¬ 𝑎 = 𝑐 → ¬ 𝑥 ∈ ∪ 𝑏 ∈ 𝑋 𝐶))
14	13	impancom 457	. . . . . . . . 9 ⊢ ((𝜑 ∧ ¬ 𝑎 = 𝑐) → (∃𝑏 ∈ 𝑊 𝑥 ∈ 𝐴 → ¬ 𝑥 ∈ ∪ 𝑏 ∈ 𝑋 𝐶))
15	1, 14	biimtrid 245	. . . . . . . 8 ⊢ ((𝜑 ∧ ¬ 𝑎 = 𝑐) → (𝑥 ∈ ∪ 𝑏 ∈ 𝑊 𝐴 → ¬ 𝑥 ∈ ∪ 𝑏 ∈ 𝑋 𝐶))
16	15	ralrimiv 3158	. . . . . . 7 ⊢ ((𝜑 ∧ ¬ 𝑎 = 𝑐) → ∀𝑥 ∈ ∪ 𝑏 ∈ 𝑊 𝐴 ¬ 𝑥 ∈ ∪ 𝑏 ∈ 𝑋 𝐶)
17		disj 4410	. . . . . . 7 ⊢ ((∪ 𝑏 ∈ 𝑊 𝐴 ∩ ∪ 𝑏 ∈ 𝑋 𝐶) = ∅ ↔ ∀𝑥 ∈ ∪ 𝑏 ∈ 𝑊 𝐴 ¬ 𝑥 ∈ ∪ 𝑏 ∈ 𝑋 𝐶)
18	16, 17	sylibr 237	. . . . . 6 ⊢ ((𝜑 ∧ ¬ 𝑎 = 𝑐) → (∪ 𝑏 ∈ 𝑊 𝐴 ∩ ∪ 𝑏 ∈ 𝑋 𝐶) = ∅)
19	18	ex 418	. . . . 5 ⊢ (𝜑 → (¬ 𝑎 = 𝑐 → (∪ 𝑏 ∈ 𝑊 𝐴 ∩ ∪ 𝑏 ∈ 𝑋 𝐶) = ∅))
20	19	orrd 877	. . . 4 ⊢ (𝜑 → (𝑎 = 𝑐 ∨ (∪ 𝑏 ∈ 𝑊 𝐴 ∩ ∪ 𝑏 ∈ 𝑋 𝐶) = ∅))
21	20	a1d 26	. . 3 ⊢ (𝜑 → ((𝑎 ∈ 𝑉 ∧ 𝑐 ∈ 𝑉) → (𝑎 = 𝑐 ∨ (∪ 𝑏 ∈ 𝑊 𝐴 ∩ ∪ 𝑏 ∈ 𝑋 𝐶) = ∅)))
22	21	ralrimivv 3208	. 2 ⊢ (𝜑 → ∀𝑎 ∈ 𝑉 ∀𝑐 ∈ 𝑉 (𝑎 = 𝑐 ∨ (∪ 𝑏 ∈ 𝑊 𝐴 ∩ ∪ 𝑏 ∈ 𝑋 𝐶) = ∅))
23		disjiund.3	. . 3 ⊢ (𝑎 = 𝑐 → 𝑊 = 𝑋)
24		disjiund.1	. . 3 ⊢ (𝑎 = 𝑐 → 𝐴 = 𝐶)
25	23, 24	disjiunb 5101	. 2 ⊢ (Disj 𝑎 ∈ 𝑉 ∪ 𝑏 ∈ 𝑊 𝐴 ↔ ∀𝑎 ∈ 𝑉 ∀𝑐 ∈ 𝑉 (𝑎 = 𝑐 ∨ (∪ 𝑏 ∈ 𝑊 𝐴 ∩ ∪ 𝑏 ∈ 𝑋 𝐶) = ∅))
26	22, 25	sylibr 237	1 ⊢ (𝜑 → Disj 𝑎 ∈ 𝑉 ∪ 𝑏 ∈ 𝑊 𝐴)

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ∧ wa 401   ∨ wo 861   ∧ w3a 1103   = wceq 1570   ∈ wcel 2146  ∀wral 3081  ∃wrex 3091   ∩ cin 3905  ∅c0 4286  ∪ ciun 4958  Disj wdisj 5078

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 2148  ax-9 2156  ax-11 2195  ax-ext 2737

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-mo 2569  df-clab 2744  df-cleq 2757  df-clel 2840  df-ral 3082  df-rex 3092  df-rmo 3371  df-v 3459  df-dif 3909  df-in 3913  df-ss 3923  df-nul 4287  df-iun 4960  df-disj 5079

This theorem is used by:  2wspiundisj  30384