Theorem disjf1 45542

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–1-1→𝑉)

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 1916	. . . . . . 7 ⊢ Ⅎ𝑥 𝑦 ∈ 𝐴
3	1, 2	nfan 1901	. . . . . 6 ⊢ Ⅎ𝑥(𝜑 ∧ 𝑦 ∈ 𝐴)
4		nfcsb1v 3875	. . . . . . 7 ⊢ Ⅎ𝑥⦋𝑦 / 𝑥⦌𝐵
5		nfcv 2899	. . . . . . 7 ⊢ Ⅎ𝑥𝑉
6	4, 5	nfel 2914	. . . . . 6 ⊢ Ⅎ𝑥⦋𝑦 / 𝑥⦌𝐵 ∈ 𝑉
7	3, 6	nfim 1898	. . . . 5 ⊢ Ⅎ𝑥((𝜑 ∧ 𝑦 ∈ 𝐴) → ⦋𝑦 / 𝑥⦌𝐵 ∈ 𝑉)
8		eleq1w 2820	. . . . . . 7 ⊢ (𝑥 = 𝑦 → (𝑥 ∈ 𝐴 ↔ 𝑦 ∈ 𝐴))
9	8	anbi2d 631	. . . . . 6 ⊢ (𝑥 = 𝑦 → ((𝜑 ∧ 𝑥 ∈ 𝐴) ↔ (𝜑 ∧ 𝑦 ∈ 𝐴)))
10		csbeq1a 3865	. . . . . . 7 ⊢ (𝑥 = 𝑦 → 𝐵 = ⦋𝑦 / 𝑥⦌𝐵)
11	10	eleq1d 2822	. . . . . 6 ⊢ (𝑥 = 𝑦 → (𝐵 ∈ 𝑉 ↔ ⦋𝑦 / 𝑥⦌𝐵 ∈ 𝑉))
12	9, 11	imbi12d 344	. . . . 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 2248	. . . 4 ⊢ ((𝜑 ∧ 𝑦 ∈ 𝐴) → ⦋𝑦 / 𝑥⦌𝐵 ∈ 𝑉)
15	14	ralrimiva 3130	. . 3 ⊢ (𝜑 → ∀𝑦 ∈ 𝐴 ⦋𝑦 / 𝑥⦌𝐵 ∈ 𝑉)
16		inidm 4181	. . . . . . . . 9 ⊢ (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑦 / 𝑥⦌𝐵) = ⦋𝑦 / 𝑥⦌𝐵
17	16	eqcomi 2746	. . . . . . . 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 4168	. . . . . . . 8 ⊢ (⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵 → (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑦 / 𝑥⦌𝐵) = (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑧 / 𝑥⦌𝐵))
20	19	ad2antlr 728	. . . . . . 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 2899	. . . . . . . . . . 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 5077	. . . . . . . . . 10 ⊢ (Disj 𝑥 ∈ 𝐴 𝐵 ↔ Disj 𝑤 ∈ 𝐴 ⦋𝑤 / 𝑥⦌𝐵)
26	21, 25	sylib 218	. . . . . . . . 9 ⊢ (𝜑 → Disj 𝑤 ∈ 𝐴 ⦋𝑤 / 𝑥⦌𝐵)
27	26	ad3antrrr 731	. . . . . . . 8 ⊢ ((((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) ∧ ¬ 𝑦 = 𝑧) → Disj 𝑤 ∈ 𝐴 ⦋𝑤 / 𝑥⦌𝐵)
28		simpllr 776	. . . . . . . 8 ⊢ ((((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) ∧ ¬ 𝑦 = 𝑧) → (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴))
29		neqne 2941	. . . . . . . . 9 ⊢ (¬ 𝑦 = 𝑧 → 𝑦 ≠ 𝑧)
30	29	adantl 481	. . . . . . . 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 5084	. . . . . . . 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 1374	. . . . . . 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 2776	. . . . . 6 ⊢ ((((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) ∧ ¬ 𝑦 = 𝑧) → ⦋𝑦 / 𝑥⦌𝐵 = ∅)
36		nfcv 2899	. . . . . . . . . . . 12 ⊢ Ⅎ𝑥∅
37	4, 36	nfne 3034	. . . . . . . . . . 11 ⊢ Ⅎ𝑥⦋𝑦 / 𝑥⦌𝐵 ≠ ∅
38	3, 37	nfim 1898	. . . . . . . . . 10 ⊢ Ⅎ𝑥((𝜑 ∧ 𝑦 ∈ 𝐴) → ⦋𝑦 / 𝑥⦌𝐵 ≠ ∅)
39	10	neeq1d 2992	. . . . . . . . . . 11 ⊢ (𝑥 = 𝑦 → (𝐵 ≠ ∅ ↔ ⦋𝑦 / 𝑥⦌𝐵 ≠ ∅))
40	9, 39	imbi12d 344	. . . . . . . . . 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 2248	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝑦 ∈ 𝐴) → ⦋𝑦 / 𝑥⦌𝐵 ≠ ∅)
43	42	adantrr 718	. . . . . . . 8 ⊢ ((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → ⦋𝑦 / 𝑥⦌𝐵 ≠ ∅)
44	43	ad2antrr 727	. . . . . . 7 ⊢ ((((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) ∧ ¬ 𝑦 = 𝑧) → ⦋𝑦 / 𝑥⦌𝐵 ≠ ∅)
45	44	neneqd 2938	. . . . . 6 ⊢ ((((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) ∧ ¬ 𝑦 = 𝑧) → ¬ ⦋𝑦 / 𝑥⦌𝐵 = ∅)
46	35, 45	condan 818	. . . . 5 ⊢ (((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) ∧ ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵) → 𝑦 = 𝑧)
47	46	ex 412	. . . 4 ⊢ ((𝜑 ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → (⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵 → 𝑦 = 𝑧))
48	47	ralrimivva 3181	. . 3 ⊢ (𝜑 → ∀𝑦 ∈ 𝐴 ∀𝑧 ∈ 𝐴 (⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵 → 𝑦 = 𝑧))
49	15, 48	jca 511	. 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 2899	. . . . 5 ⊢ Ⅎ𝑦𝐵
52	51, 4, 10	cbvmpt 5202	. . . 4 ⊢ (𝑥 ∈ 𝐴 ↦ 𝐵) = (𝑦 ∈ 𝐴 ↦ ⦋𝑦 / 𝑥⦌𝐵)
53	50, 52	eqtri 2760	. . 3 ⊢ 𝐹 = (𝑦 ∈ 𝐴 ↦ ⦋𝑦 / 𝑥⦌𝐵)
54		csbeq1 3854	. . 3 ⊢ (𝑦 = 𝑧 → ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵)
55	53, 54	f1mpt 7217	. 2 ⊢ (𝐹:𝐴–1-1→𝑉 ↔ (∀𝑦 ∈ 𝐴 ⦋𝑦 / 𝑥⦌𝐵 ∈ 𝑉 ∧ ∀𝑦 ∈ 𝐴 ∀𝑧 ∈ 𝐴 (⦋𝑦 / 𝑥⦌𝐵 = ⦋𝑧 / 𝑥⦌𝐵 → 𝑦 = 𝑧)))
56	49, 55	sylibr 234	1 ⊢ (𝜑 → 𝐹:𝐴–1-1→𝑉)

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 395   = wceq 1542  Ⅎwnf 1785   ∈ wcel 2114   ≠ wne 2933  ∀wral 3052  ⦋csb 3851   ∩ cin 3902  ∅c0 4287  Disj wdisj 5067   ↦ cmpt 5181  –1-1→wf1 6497

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-8 2116  ax-9 2124  ax-10 2147  ax-11 2163  ax-12 2185  ax-ext 2709  ax-sep 5243  ax-nul 5253  ax-pr 5379

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3an 1089  df-tru 1545  df-fal 1555  df-ex 1782  df-nf 1786  df-sb 2069  df-mo 2540  df-eu 2570  df-clab 2716  df-cleq 2729  df-clel 2812  df-nfc 2886  df-ne 2934  df-ral 3053  df-rex 3063  df-rmo 3352  df-rab 3402  df-v 3444  df-sbc 3743  df-csb 3852  df-dif 3906  df-un 3908  df-in 3910  df-ss 3920  df-nul 4288  df-if 4482  df-sn 4583  df-pr 4585  df-op 4589  df-uni 4866  df-disj 5068  df-br 5101  df-opab 5163  df-mpt 5182  df-id 5527  df-xp 5638  df-rel 5639  df-cnv 5640  df-co 5641  df-dm 5642  df-rn 5643  df-res 5644  df-ima 5645  df-iota 6456  df-fun 6502  df-fn 6503  df-f 6504  df-f1 6505  df-fv 6508

This theorem is referenced by:  disjf1o  45550  meadjiunlem  46823