Theorem disjiun 3995

Description: A disjoint collection yields disjoint indexed unions for disjoint index sets. (Contributed by Mario Carneiro, 26-Mar-2015.) (Revised by Mario Carneiro, 14-Nov-2016.)

Assertion

Ref	Expression
disjiun	⊢ ((Disj 𝑥 ∈ 𝐴 𝐵 ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴 ∧ (𝐶 ∩ 𝐷) = ∅)) → (∪ 𝑥 ∈ 𝐶 𝐵 ∩ ∪ 𝑥 ∈ 𝐷 𝐵) = ∅)

Distinct variable groups:   𝑥,𝐴   𝑥,𝐶   𝑥,𝐷

Allowed substitution hint:   𝐵(𝑥)

Proof of Theorem disjiun

Dummy variables 𝑢 𝑣 𝑤 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		df-disj 3978	. . . 4 ⊢ (Disj 𝑥 ∈ 𝐴 𝐵 ↔ ∀𝑦∃*𝑥 ∈ 𝐴 𝑦 ∈ 𝐵)
2		elin 3318	. . . . . . . . . 10 ⊢ (𝑦 ∈ (∪ 𝑥 ∈ 𝐶 𝐵 ∩ ∪ 𝑥 ∈ 𝐷 𝐵) ↔ (𝑦 ∈ ∪ 𝑥 ∈ 𝐶 𝐵 ∧ 𝑦 ∈ ∪ 𝑥 ∈ 𝐷 𝐵))
3		eliun 3888	. . . . . . . . . . 11 ⊢ (𝑦 ∈ ∪ 𝑥 ∈ 𝐶 𝐵 ↔ ∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵)
4		eliun 3888	. . . . . . . . . . 11 ⊢ (𝑦 ∈ ∪ 𝑥 ∈ 𝐷 𝐵 ↔ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)
5	3, 4	anbi12i 460	. . . . . . . . . 10 ⊢ ((𝑦 ∈ ∪ 𝑥 ∈ 𝐶 𝐵 ∧ 𝑦 ∈ ∪ 𝑥 ∈ 𝐷 𝐵) ↔ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵))
6	2, 5	bitri 184	. . . . . . . . 9 ⊢ (𝑦 ∈ (∪ 𝑥 ∈ 𝐶 𝐵 ∩ ∪ 𝑥 ∈ 𝐷 𝐵) ↔ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵))
7		nfv 1528	. . . . . . . . . . . 12 ⊢ Ⅎ𝑤 𝑦 ∈ 𝐵
8	7	rmo3 3054	. . . . . . . . . . 11 ⊢ (∃*𝑥 ∈ 𝐴 𝑦 ∈ 𝐵 ↔ ∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤))
9		simprl 529	. . . . . . . . . . . . . 14 ⊢ (((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) → ∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵)
10		nfv 1528	. . . . . . . . . . . . . . 15 ⊢ Ⅎ𝑢 𝑦 ∈ 𝐵
11		nfcsb1v 3090	. . . . . . . . . . . . . . . 16 ⊢ Ⅎ𝑥⦋𝑢 / 𝑥⦌𝐵
12	11	nfcri 2313	. . . . . . . . . . . . . . 15 ⊢ Ⅎ𝑥 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵
13		csbeq1a 3066	. . . . . . . . . . . . . . . 16 ⊢ (𝑥 = 𝑢 → 𝐵 = ⦋𝑢 / 𝑥⦌𝐵)
14	13	eleq2d 2247	. . . . . . . . . . . . . . 15 ⊢ (𝑥 = 𝑢 → (𝑦 ∈ 𝐵 ↔ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵))
15	10, 12, 14	cbvrex 2700	. . . . . . . . . . . . . 14 ⊢ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ↔ ∃𝑢 ∈ 𝐶 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)
16	9, 15	sylib 122	. . . . . . . . . . . . 13 ⊢ (((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) → ∃𝑢 ∈ 𝐶 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)
17		simplrr 536	. . . . . . . . . . . . . . 15 ⊢ ((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) → ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)
18		nfv 1528	. . . . . . . . . . . . . . . 16 ⊢ Ⅎ𝑣 𝑦 ∈ 𝐵
19		nfcsb1v 3090	. . . . . . . . . . . . . . . . 17 ⊢ Ⅎ𝑥⦋𝑣 / 𝑥⦌𝐵
20	19	nfcri 2313	. . . . . . . . . . . . . . . 16 ⊢ Ⅎ𝑥 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵
21		csbeq1a 3066	. . . . . . . . . . . . . . . . 17 ⊢ (𝑥 = 𝑣 → 𝐵 = ⦋𝑣 / 𝑥⦌𝐵)
22	21	eleq2d 2247	. . . . . . . . . . . . . . . 16 ⊢ (𝑥 = 𝑣 → (𝑦 ∈ 𝐵 ↔ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵))
23	18, 20, 22	cbvrex 2700	. . . . . . . . . . . . . . 15 ⊢ (∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵 ↔ ∃𝑣 ∈ 𝐷 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)
24	17, 23	sylib 122	. . . . . . . . . . . . . 14 ⊢ ((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) → ∃𝑣 ∈ 𝐷 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)
25		simplrl 535	. . . . . . . . . . . . . . 15 ⊢ (((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) ∧ (𝑣 ∈ 𝐷 ∧ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)) → 𝑢 ∈ 𝐶)
26		simprl 529	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) → 𝐶 ⊆ 𝐴)
27	26	ad3antrrr 492	. . . . . . . . . . . . . . . . . . 19 ⊢ (((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) ∧ (𝑣 ∈ 𝐷 ∧ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)) → 𝐶 ⊆ 𝐴)
28	27, 25	sseldd 3156	. . . . . . . . . . . . . . . . . 18 ⊢ (((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) ∧ (𝑣 ∈ 𝐷 ∧ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)) → 𝑢 ∈ 𝐴)
29		simprr 531	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) → 𝐷 ⊆ 𝐴)
30	29	ad3antrrr 492	. . . . . . . . . . . . . . . . . . 19 ⊢ (((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) ∧ (𝑣 ∈ 𝐷 ∧ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)) → 𝐷 ⊆ 𝐴)
31		simprl 529	. . . . . . . . . . . . . . . . . . 19 ⊢ (((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) ∧ (𝑣 ∈ 𝐷 ∧ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)) → 𝑣 ∈ 𝐷)
32	30, 31	sseldd 3156	. . . . . . . . . . . . . . . . . 18 ⊢ (((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) ∧ (𝑣 ∈ 𝐷 ∧ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)) → 𝑣 ∈ 𝐴)
33	28, 32	jca 306	. . . . . . . . . . . . . . . . 17 ⊢ (((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) ∧ (𝑣 ∈ 𝐷 ∧ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)) → (𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴))
34		simp-4l 541	. . . . . . . . . . . . . . . . 17 ⊢ (((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) ∧ (𝑣 ∈ 𝐷 ∧ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)) → ∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤))
35		simplrr 536	. . . . . . . . . . . . . . . . . 18 ⊢ (((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) ∧ (𝑣 ∈ 𝐷 ∧ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)) → 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)
36		simprr 531	. . . . . . . . . . . . . . . . . . 19 ⊢ (((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) ∧ (𝑣 ∈ 𝐷 ∧ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)) → 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)
37	20, 22	sbie 1791	. . . . . . . . . . . . . . . . . . 19 ⊢ ([𝑣 / 𝑥]𝑦 ∈ 𝐵 ↔ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)
38	36, 37	sylibr 134	. . . . . . . . . . . . . . . . . 18 ⊢ (((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) ∧ (𝑣 ∈ 𝐷 ∧ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)) → [𝑣 / 𝑥]𝑦 ∈ 𝐵)
39	35, 38	jca 306	. . . . . . . . . . . . . . . . 17 ⊢ (((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) ∧ (𝑣 ∈ 𝐷 ∧ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)) → (𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵 ∧ [𝑣 / 𝑥]𝑦 ∈ 𝐵))
40		nfs1v 1939	. . . . . . . . . . . . . . . . . . . 20 ⊢ Ⅎ𝑥[𝑤 / 𝑥]𝑦 ∈ 𝐵
41	12, 40	nfan 1565	. . . . . . . . . . . . . . . . . . 19 ⊢ Ⅎ𝑥(𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵)
42		nfv 1528	. . . . . . . . . . . . . . . . . . 19 ⊢ Ⅎ𝑥 𝑢 = 𝑤
43	41, 42	nfim 1572	. . . . . . . . . . . . . . . . . 18 ⊢ Ⅎ𝑥((𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑢 = 𝑤)
44		nfv 1528	. . . . . . . . . . . . . . . . . 18 ⊢ Ⅎ𝑤((𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵 ∧ [𝑣 / 𝑥]𝑦 ∈ 𝐵) → 𝑢 = 𝑣)
45	14	anbi1d 465	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑥 = 𝑢 → ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) ↔ (𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵)))
46		equequ1 1712	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑥 = 𝑢 → (𝑥 = 𝑤 ↔ 𝑢 = 𝑤))
47	45, 46	imbi12d 234	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑥 = 𝑢 → (((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ↔ ((𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑢 = 𝑤)))
48		sbequ 1840	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑤 = 𝑣 → ([𝑤 / 𝑥]𝑦 ∈ 𝐵 ↔ [𝑣 / 𝑥]𝑦 ∈ 𝐵))
49	48	anbi2d 464	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑤 = 𝑣 → ((𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) ↔ (𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵 ∧ [𝑣 / 𝑥]𝑦 ∈ 𝐵)))
50		equequ2 1713	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑤 = 𝑣 → (𝑢 = 𝑤 ↔ 𝑢 = 𝑣))
51	49, 50	imbi12d 234	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑤 = 𝑣 → (((𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑢 = 𝑤) ↔ ((𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵 ∧ [𝑣 / 𝑥]𝑦 ∈ 𝐵) → 𝑢 = 𝑣)))
52	43, 44, 47, 51	rspc2 2852	. . . . . . . . . . . . . . . . 17 ⊢ ((𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴) → (∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) → ((𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵 ∧ [𝑣 / 𝑥]𝑦 ∈ 𝐵) → 𝑢 = 𝑣)))
53	33, 34, 39, 52	syl3c 63	. . . . . . . . . . . . . . . 16 ⊢ (((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) ∧ (𝑣 ∈ 𝐷 ∧ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)) → 𝑢 = 𝑣)
54	53, 31	eqeltrd 2254	. . . . . . . . . . . . . . 15 ⊢ (((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) ∧ (𝑣 ∈ 𝐷 ∧ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)) → 𝑢 ∈ 𝐷)
55		inelcm 3483	. . . . . . . . . . . . . . 15 ⊢ ((𝑢 ∈ 𝐶 ∧ 𝑢 ∈ 𝐷) → (𝐶 ∩ 𝐷) ≠ ∅)
56	25, 54, 55	syl2anc 411	. . . . . . . . . . . . . 14 ⊢ (((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) ∧ (𝑣 ∈ 𝐷 ∧ 𝑦 ∈ ⦋𝑣 / 𝑥⦌𝐵)) → (𝐶 ∩ 𝐷) ≠ ∅)
57	24, 56	rexlimddv 2599	. . . . . . . . . . . . 13 ⊢ ((((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) ∧ (𝑢 ∈ 𝐶 ∧ 𝑦 ∈ ⦋𝑢 / 𝑥⦌𝐵)) → (𝐶 ∩ 𝐷) ≠ ∅)
58	16, 57	rexlimddv 2599	. . . . . . . . . . . 12 ⊢ (((∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴)) ∧ (∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵)) → (𝐶 ∩ 𝐷) ≠ ∅)
59	58	exp31 364	. . . . . . . . . . 11 ⊢ (∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 ((𝑦 ∈ 𝐵 ∧ [𝑤 / 𝑥]𝑦 ∈ 𝐵) → 𝑥 = 𝑤) → ((𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴) → ((∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵) → (𝐶 ∩ 𝐷) ≠ ∅)))
60	8, 59	sylbi 121	. . . . . . . . . 10 ⊢ (∃*𝑥 ∈ 𝐴 𝑦 ∈ 𝐵 → ((𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴) → ((∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵) → (𝐶 ∩ 𝐷) ≠ ∅)))
61	60	impcom 125	. . . . . . . . 9 ⊢ (((𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴) ∧ ∃*𝑥 ∈ 𝐴 𝑦 ∈ 𝐵) → ((∃𝑥 ∈ 𝐶 𝑦 ∈ 𝐵 ∧ ∃𝑥 ∈ 𝐷 𝑦 ∈ 𝐵) → (𝐶 ∩ 𝐷) ≠ ∅))
62	6, 61	biimtrid 152	. . . . . . . 8 ⊢ (((𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴) ∧ ∃*𝑥 ∈ 𝐴 𝑦 ∈ 𝐵) → (𝑦 ∈ (∪ 𝑥 ∈ 𝐶 𝐵 ∩ ∪ 𝑥 ∈ 𝐷 𝐵) → (𝐶 ∩ 𝐷) ≠ ∅))
63	62	necon2bd 2405	. . . . . . 7 ⊢ (((𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴) ∧ ∃*𝑥 ∈ 𝐴 𝑦 ∈ 𝐵) → ((𝐶 ∩ 𝐷) = ∅ → ¬ 𝑦 ∈ (∪ 𝑥 ∈ 𝐶 𝐵 ∩ ∪ 𝑥 ∈ 𝐷 𝐵)))
64	63	impancom 260	. . . . . 6 ⊢ (((𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴) ∧ (𝐶 ∩ 𝐷) = ∅) → (∃*𝑥 ∈ 𝐴 𝑦 ∈ 𝐵 → ¬ 𝑦 ∈ (∪ 𝑥 ∈ 𝐶 𝐵 ∩ ∪ 𝑥 ∈ 𝐷 𝐵)))
65	64	3impa 1194	. . . . 5 ⊢ ((𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴 ∧ (𝐶 ∩ 𝐷) = ∅) → (∃*𝑥 ∈ 𝐴 𝑦 ∈ 𝐵 → ¬ 𝑦 ∈ (∪ 𝑥 ∈ 𝐶 𝐵 ∩ ∪ 𝑥 ∈ 𝐷 𝐵)))
66	65	alimdv 1879	. . . 4 ⊢ ((𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴 ∧ (𝐶 ∩ 𝐷) = ∅) → (∀𝑦∃*𝑥 ∈ 𝐴 𝑦 ∈ 𝐵 → ∀𝑦 ¬ 𝑦 ∈ (∪ 𝑥 ∈ 𝐶 𝐵 ∩ ∪ 𝑥 ∈ 𝐷 𝐵)))
67	1, 66	biimtrid 152	. . 3 ⊢ ((𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴 ∧ (𝐶 ∩ 𝐷) = ∅) → (Disj 𝑥 ∈ 𝐴 𝐵 → ∀𝑦 ¬ 𝑦 ∈ (∪ 𝑥 ∈ 𝐶 𝐵 ∩ ∪ 𝑥 ∈ 𝐷 𝐵)))
68	67	impcom 125	. 2 ⊢ ((Disj 𝑥 ∈ 𝐴 𝐵 ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴 ∧ (𝐶 ∩ 𝐷) = ∅)) → ∀𝑦 ¬ 𝑦 ∈ (∪ 𝑥 ∈ 𝐶 𝐵 ∩ ∪ 𝑥 ∈ 𝐷 𝐵))
69		eq0 3441	. 2 ⊢ ((∪ 𝑥 ∈ 𝐶 𝐵 ∩ ∪ 𝑥 ∈ 𝐷 𝐵) = ∅ ↔ ∀𝑦 ¬ 𝑦 ∈ (∪ 𝑥 ∈ 𝐶 𝐵 ∩ ∪ 𝑥 ∈ 𝐷 𝐵))
70	68, 69	sylibr 134	1 ⊢ ((Disj 𝑥 ∈ 𝐴 𝐵 ∧ (𝐶 ⊆ 𝐴 ∧ 𝐷 ⊆ 𝐴 ∧ (𝐶 ∩ 𝐷) = ∅)) → (∪ 𝑥 ∈ 𝐶 𝐵 ∩ ∪ 𝑥 ∈ 𝐷 𝐵) = ∅)

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 104   ∧ w3a 978  ∀wal 1351   = wceq 1353  [wsb 1762   ∈ wcel 2148   ≠ wne 2347  ∀wral 2455  ∃wrex 2456  ∃*wrmo 2458  ⦋csb 3057   ∩ cin 3128   ⊆ wss 3129  ∅c0 3422  ∪ ciun 3884  Disj wdisj 3977

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 614  ax-in2 615  ax-io 709  ax-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-ext 2159

This theorem depends on definitions:  df-bi 117  df-3an 980  df-tru 1356  df-nf 1461  df-sb 1763  df-eu 2029  df-mo 2030  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-ne 2348  df-ral 2460  df-rex 2461  df-rmo 2463  df-v 2739  df-sbc 2963  df-csb 3058  df-dif 3131  df-in 3135  df-ss 3142  df-nul 3423  df-iun 3886  df-disj 3978

This theorem is referenced by:  iunfidisj  6939  fsumiun  11469