Theorem disjf1 46471

Description: A 1 to 1 mapping built from disjoint, nonempty sets. (Contributed by Glauco Siliprandi, 17-Aug-2020.)

Hypotheses

Ref	Expression
disjf1.xph	⊢ Ⅎ𝑥𝜑
disjf1.f	⊢ 𝐹 = (𝑥 ∈ 𝐴 ↦ 𝐵)
disjf1.b	⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → 𝐵 ∈ 𝑉)
disjf1.n0	⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → 𝐵 ≠ ∅)
disjf1.dj	⊢ (𝜑 → Disj 𝑥 ∈ 𝐴 𝐵)

Assertion

Ref	Expression
disjf1	⊢ (𝜑 → 𝐹:𝐴⟶1-1𝑉)

Distinct variable groups:   𝑥,𝐴   𝑥,𝑉

Allowed substitution hints:   𝜑(𝑥)   𝐵(𝑥)   𝐹(𝑥)

Proof of Theorem disjf1

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

Step	Hyp	Ref	Expression
1		disjf1.xph	. . . . . . 7 ⊢ Ⅎ𝑥𝜑
2		nfv 1949	. . . . . . 7 ⊢ Ⅎ𝑥 𝑦 ∈ 𝐴
3	1, 2	nfan 1934	. . . . . 6 ⊢ Ⅎ𝑥(𝜑 ∧ 𝑦 ∈ 𝐴)
4		nfcsb1v 3875	. . . . . . 7 ⊢ Ⅎ𝑥⦋𝑦 / 𝑥⦌𝐵
5		nfcv 2926	. . . . . . 7 ⊢ Ⅎ𝑥𝑉
6	4, 5	nfel 2940	. . . . . 6 ⊢ Ⅎ𝑥⦋𝑦 / 𝑥⦌𝐵 ∈ 𝑉
7	3, 6	nfim 1931	. . . . 5 ⊢ Ⅎ𝑥((𝜑 ∧ 𝑦 ∈ 𝐴) → ⦋𝑦 / 𝑥⦌𝐵 ∈ 𝑉)
8		eleq1w 2847	. . . . . . 7 ⊢ (𝑥 = 𝑦 → (𝑥 ∈ 𝐴 ↔ 𝑦 ∈ 𝐴))
9	8	anbi2d 642	. . . . . 6 ⊢ (𝑥 = 𝑦 → ((𝜑 ∧ 𝑥 ∈ 𝐴) ↔ (𝜑 ∧ 𝑦 ∈ 𝐴)))
10		csbeq1a 3865	. . . . . . 7 ⊢ (𝑥 = 𝑦 → 𝐵 = ⦋𝑦 / 𝑥⦌𝐵)
11	10	eleq1d 2849	. . . . . 6 ⊢ (𝑥 = 𝑦 → (𝐵 ∈ 𝑉 ↔ ⦋𝑦 / 𝑥⦌𝐵 ∈ 𝑉))
12	9, 11	imbi12d 347	. . . . 5 ⊢ (𝑥 = 𝑦 → (((𝜑 ∧ 𝑥 ∈ 𝐴) → 𝐵 ∈ 𝑉) ↔ ((𝜑 ∧ 𝑦 ∈ 𝐴) → ⦋𝑦 / 𝑥⦌𝐵 ∈ 𝑉)))
13		disjf1.b	. . . . 5 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → 𝐵 ∈ 𝑉)
14	7, 12, 13	chvarfv 2280	. . . 4 ⊢ ((𝜑 ∧ 𝑦 ∈ 𝐴) → ⦋𝑦 / 𝑥⦌𝐵 ∈ 𝑉)
15	14	ralrimiva 3158	. . 3 ⊢ (𝜑 → ∀𝑦 ∈ 𝐴 ⦋𝑦 / 𝑥⦌𝐵 ∈ 𝑉)
16		inidm 4126	. . . . . . . . 9 ⊢ (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑦 / 𝑥⦌𝐵) = ⦋𝑦 / 𝑥⦌𝐵
17	16	eqcomi 2772	. . . . . . . 8 ⊢ ⦋𝑦 / 𝑥⦌𝐵 = (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑦 / 𝑥⦌𝐵)
18	17	a1i 11	. . . . . . 7 ⊢ ((((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) ∧ ¬ 𝑦 = 𝑧) → ⦋𝑦 / 𝑥⦌𝐵 = (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑦 / 𝑥⦌𝐵))
19		ineq2 4114	. . . . . . . 8 ⊢ (⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵 → (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑦 / 𝑥⦌𝐵) = (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑧 / 𝑥⦌𝐵))
20	19	ad2antlr 740	. . . . . . 7 ⊢ ((((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) ∧ ¬ 𝑦 = 𝑧) → (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑦 / 𝑥⦌𝐵) = (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑧 / 𝑥⦌𝐵))
21		disjf1.dj	. . . . . . . . . 10 ⊢ (𝜑 → Disj 𝑥 ∈ 𝐴 𝐵)
22		nfcv 2926	. . . . . . . . . . 11 ⊢ Ⅎ𝑤𝐵
23		nfcsb1v 3875	. . . . . . . . . . 11 ⊢ Ⅎ𝑥⦋𝑤 / 𝑥⦌𝐵
24		csbeq1a 3865	. . . . . . . . . . 11 ⊢ (𝑥 = 𝑤 → 𝐵 = ⦋𝑤 / 𝑥⦌𝐵)
25	22, 23, 24	cbvdisj 5085	. . . . . . . . . 10 ⊢ (Disj 𝑥 ∈ 𝐴 𝐵 ↔ Disj 𝑤 ∈ 𝐴 ⦋𝑤 / 𝑥⦌𝐵)
26	21, 25	sylib 221	. . . . . . . . 9 ⊢ (𝜑 → Disj 𝑤 ∈ 𝐴 ⦋𝑤 / 𝑥⦌𝐵)
27	26	ad3antrrr 743	. . . . . . . 8 ⊢ ((((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) ∧ ¬ 𝑦 = 𝑧) → Disj 𝑤 ∈ 𝐴 ⦋𝑤 / 𝑥⦌𝐵)
28		simpllr 788	. . . . . . . 8 ⊢ ((((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) ∧ ¬ 𝑦 = 𝑧) → (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴))
29		neqne 2967	. . . . . . . . 9 ⊢ (¬ 𝑦 = 𝑧 → 𝑦 ≠ 𝑧)
30	29	adantl 487	. . . . . . . 8 ⊢ ((((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) ∧ ¬ 𝑦 = 𝑧) → 𝑦 ≠ 𝑧)
31		csbeq1 3854	. . . . . . . . 9 ⊢ (𝑤 = 𝑦 → ⦋𝑤 / 𝑥⦌𝐵 = ⦋𝑦 / 𝑥⦌𝐵)
32		csbeq1 3854	. . . . . . . . 9 ⊢ (𝑤 = 𝑧 → ⦋𝑤 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵)
33	31, 32	disji2 5092	. . . . . . . 8 ⊢ ((Disj 𝑤 ∈ 𝐴 ⦋𝑤 / 𝑥⦌𝐵 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴) ∧ 𝑦 ≠ 𝑧) → (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑧 / 𝑥⦌𝐵) = ∅)
34	27, 28, 30, 33	syl3anc 1399	. . . . . . 7 ⊢ ((((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) ∧ ¬ 𝑦 = 𝑧) → (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑧 / 𝑥⦌𝐵) = ∅)
35	18, 20, 34	3eqtrd 2802	. . . . . 6 ⊢ ((((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) ∧ ¬ 𝑦 = 𝑧) → ⦋𝑦 / 𝑥⦌𝐵 = ∅)
36		nfcv 2926	. . . . . . . . . . . 12 ⊢ Ⅎ𝑥∅
37	4, 36	nfne 3062	. . . . . . . . . . 11 ⊢ Ⅎ𝑥⦋𝑦 / 𝑥⦌𝐵 ≠ ∅
38	3, 37	nfim 1931	. . . . . . . . . 10 ⊢ Ⅎ𝑥((𝜑 ∧ 𝑦 ∈ 𝐴) → ⦋𝑦 / 𝑥⦌𝐵 ≠ ∅)
39	10	neeq1d 3018	. . . . . . . . . . 11 ⊢ (𝑥 = 𝑦 → (𝐵 ≠ ∅ ↔ ⦋𝑦 / 𝑥⦌𝐵 ≠ ∅))
40	9, 39	imbi12d 347	. . . . . . . . . 10 ⊢ (𝑥 = 𝑦 → (((𝜑 ∧ 𝑥 ∈ 𝐴) → 𝐵 ≠ ∅) ↔ ((𝜑 ∧ 𝑦 ∈ 𝐴) → ⦋𝑦 / 𝑥⦌𝐵 ≠ ∅)))
41		disjf1.n0	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → 𝐵 ≠ ∅)
42	38, 40, 41	chvarfv 2280	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝑦 ∈ 𝐴) → ⦋𝑦 / 𝑥⦌𝐵 ≠ ∅)
43	42	adantrr 730	. . . . . . . 8 ⊢ ((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → ⦋𝑦 / 𝑥⦌𝐵 ≠ ∅)
44	43	ad2antrr 739	. . . . . . 7 ⊢ ((((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) ∧ ¬ 𝑦 = 𝑧) → ⦋𝑦 / 𝑥⦌𝐵 ≠ ∅)
45	44	neneqd 2964	. . . . . 6 ⊢ ((((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) ∧ ¬ 𝑦 = 𝑧) → ¬ ⦋𝑦 / 𝑥⦌𝐵 = ∅)
46	35, 45	condan 830	. . . . 5 ⊢ (((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) → 𝑦 = 𝑧)
47	46	ex 418	. . . 4 ⊢ ((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → (⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵 → 𝑦 = 𝑧))
48	47	ralrimivva 3209	. . 3 ⊢ (𝜑 → ∀𝑦 ∈ 𝐴 ∀𝑧 ∈ 𝐴 (⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵 → 𝑦 = 𝑧))
49	15, 48	jca 521	. 2 ⊢ (𝜑 → (∀𝑦 ∈ 𝐴 ⦋𝑦 / 𝑥⦌𝐵 ∈ 𝑉 ∧ ∀𝑦 ∈ 𝐴 ∀𝑧 ∈ 𝐴 (⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵 → 𝑦 = 𝑧)))
50		disjf1.f	. . . 4 ⊢ 𝐹 = (𝑥 ∈ 𝐴 ↦ 𝐵)
51		nfcv 2926	. . . . 5 ⊢ Ⅎ𝑦𝐵
52	51, 4, 10	cbvmpt 5213	. . . 4 ⊢ (𝑥 ∈ 𝐴 ↦ 𝐵) = (𝑦 ∈ 𝐴 ↦ ⦋𝑦 / 𝑥⦌𝐵)
53	50, 52	eqtri 2786	. . 3 ⊢ 𝐹 = (𝑦 ∈ 𝐴 ↦ ⦋𝑦 / 𝑥⦌𝐵)
54		csbeq1 3854	. . 3 ⊢ (𝑦 = 𝑧 → ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵)
55	53, 54	f1mpt 7296	. 2 ⊢ (𝐹:𝐴⟶1-1𝑉 ↔ (∀𝑦 ∈ 𝐴 ⦋𝑦 / 𝑥⦌𝐵 ∈ 𝑉 ∧ ∀𝑦 ∈ 𝐴 ∀𝑧 ∈ 𝐴 (⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵 → 𝑦 = 𝑧)))
56	49, 55	sylibr 237	1 ⊢ (𝜑 → 𝐹:𝐴⟶1-1𝑉)

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ∧ wa 401   = wceq 1570  Ⅎwnf 1816   ∈ wcel 2147   ≠ wne 2959  ∀wral 3080  ⦋csb 3851   ∩ cin 4092  ∅c0 4281  Disj wdisj 5075   ↦ cmpt 5192  ⟶1-1wf1 6563

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 1945  ax-6 2002  ax-7 2043  ax-8 2149  ax-9 2157  ax-10 2180  ax-11 2197  ax-12 2216  ax-ext 2735  ax-sep 5255  ax-nul 5266  ax-pr 5398

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-nf 1817  df-sb 2102  df-mo 2567  df-eu 2597  df-clab 2742  df-cleq 2755  df-clel 2839  df-nfc 2913  df-ne 2960  df-ral 3081  df-rex 3091  df-rmo 3369  df-rab 3417  df-v 3456  df-sbc 3743  df-csb 3852  df-ss 3901  df-dif 4050  df-in 4094  df-un 4154  df-nul 4282  df-if 4486  df-sn 4589  df-pr 4591  df-op 4841  df-uni 4873  df-disj 5076  df-br 5109  df-opab 5174  df-mpt 5193  df-id 5553  df-xp 5664  df-rel 5665  df-cnv 5666  df-co 5667  df-dm 5668  df-rn 5669  df-res 5670  df-ima 5671  df-iota 6520  df-fun 6568  df-fn 6569  df-f 6570  df-f1 6571  df-fv 6574

This theorem is used by:  disjf1o  46479  meadjiunlem  47748