Theorem cnt0 21954

Description: The preimage of a T₀ topology under an injective map is T₀. (Contributed by Mario Carneiro, 25-Aug-2015.)

Assertion

Ref	Expression
cnt0	⊢ ((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) → 𝐽 ∈ Kol2)

Proof of Theorem cnt0

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

Step	Hyp	Ref	Expression
1		cntop1 21848	. . 3 ⊢ (𝐹 ∈ (𝐽 Cn 𝐾) → 𝐽 ∈ Top)
2	1	3ad2ant3 1131	. 2 ⊢ ((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) → 𝐽 ∈ Top)
3		simpl3 1189	. . . . . . . . 9 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → 𝐹 ∈ (𝐽 Cn 𝐾))
4		cnima 21873	. . . . . . . . 9 ⊢ ((𝐹 ∈ (𝐽 Cn 𝐾) ∧ 𝑤 ∈ 𝐾) → (◡𝐹 “ 𝑤) ∈ 𝐽)
5	3, 4	sylan 582	. . . . . . . 8 ⊢ ((((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) ∧ 𝑤 ∈ 𝐾) → (◡𝐹 “ 𝑤) ∈ 𝐽)
6		eleq2 2901	. . . . . . . . . 10 ⊢ (𝑧 = (◡𝐹 “ 𝑤) → (𝑥 ∈ 𝑧 ↔ 𝑥 ∈ (◡𝐹 “ 𝑤)))
7		eleq2 2901	. . . . . . . . . 10 ⊢ (𝑧 = (◡𝐹 “ 𝑤) → (𝑦 ∈ 𝑧 ↔ 𝑦 ∈ (◡𝐹 “ 𝑤)))
8	6, 7	bibi12d 348	. . . . . . . . 9 ⊢ (𝑧 = (◡𝐹 “ 𝑤) → ((𝑥 ∈ 𝑧 ↔ 𝑦 ∈ 𝑧) ↔ (𝑥 ∈ (◡𝐹 “ 𝑤) ↔ 𝑦 ∈ (◡𝐹 “ 𝑤))))
9	8	rspcv 3618	. . . . . . . 8 ⊢ ((◡𝐹 “ 𝑤) ∈ 𝐽 → (∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 ↔ 𝑦 ∈ 𝑧) → (𝑥 ∈ (◡𝐹 “ 𝑤) ↔ 𝑦 ∈ (◡𝐹 “ 𝑤))))
10	5, 9	syl 17	. . . . . . 7 ⊢ ((((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) ∧ 𝑤 ∈ 𝐾) → (∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 ↔ 𝑦 ∈ 𝑧) → (𝑥 ∈ (◡𝐹 “ 𝑤) ↔ 𝑦 ∈ (◡𝐹 “ 𝑤))))
11		simprl 769	. . . . . . . . . 10 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → 𝑥 ∈ ∪ 𝐽)
12		eqid 2821	. . . . . . . . . . . . . 14 ⊢ ∪ 𝐽 = ∪ 𝐽
13		eqid 2821	. . . . . . . . . . . . . 14 ⊢ ∪ 𝐾 = ∪ 𝐾
14	12, 13	cnf 21854	. . . . . . . . . . . . 13 ⊢ (𝐹 ∈ (𝐽 Cn 𝐾) → 𝐹:∪ 𝐽⟶∪ 𝐾)
15	3, 14	syl 17	. . . . . . . . . . . 12 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → 𝐹:∪ 𝐽⟶∪ 𝐾)
16	15	ffnd 6515	. . . . . . . . . . 11 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → 𝐹 Fn ∪ 𝐽)
17		elpreima 6828	. . . . . . . . . . 11 ⊢ (𝐹 Fn ∪ 𝐽 → (𝑥 ∈ (◡𝐹 “ 𝑤) ↔ (𝑥 ∈ ∪ 𝐽 ∧ (𝐹‘𝑥) ∈ 𝑤)))
18	16, 17	syl 17	. . . . . . . . . 10 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → (𝑥 ∈ (◡𝐹 “ 𝑤) ↔ (𝑥 ∈ ∪ 𝐽 ∧ (𝐹‘𝑥) ∈ 𝑤)))
19	11, 18	mpbirand 705	. . . . . . . . 9 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → (𝑥 ∈ (◡𝐹 “ 𝑤) ↔ (𝐹‘𝑥) ∈ 𝑤))
20		simprr 771	. . . . . . . . . 10 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → 𝑦 ∈ ∪ 𝐽)
21		elpreima 6828	. . . . . . . . . . 11 ⊢ (𝐹 Fn ∪ 𝐽 → (𝑦 ∈ (◡𝐹 “ 𝑤) ↔ (𝑦 ∈ ∪ 𝐽 ∧ (𝐹‘𝑦) ∈ 𝑤)))
22	16, 21	syl 17	. . . . . . . . . 10 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → (𝑦 ∈ (◡𝐹 “ 𝑤) ↔ (𝑦 ∈ ∪ 𝐽 ∧ (𝐹‘𝑦) ∈ 𝑤)))
23	20, 22	mpbirand 705	. . . . . . . . 9 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → (𝑦 ∈ (◡𝐹 “ 𝑤) ↔ (𝐹‘𝑦) ∈ 𝑤))
24	19, 23	bibi12d 348	. . . . . . . 8 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → ((𝑥 ∈ (◡𝐹 “ 𝑤) ↔ 𝑦 ∈ (◡𝐹 “ 𝑤)) ↔ ((𝐹‘𝑥) ∈ 𝑤 ↔ (𝐹‘𝑦) ∈ 𝑤)))
25	24	adantr 483	. . . . . . 7 ⊢ ((((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) ∧ 𝑤 ∈ 𝐾) → ((𝑥 ∈ (◡𝐹 “ 𝑤) ↔ 𝑦 ∈ (◡𝐹 “ 𝑤)) ↔ ((𝐹‘𝑥) ∈ 𝑤 ↔ (𝐹‘𝑦) ∈ 𝑤)))
26	10, 25	sylibd 241	. . . . . 6 ⊢ ((((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) ∧ 𝑤 ∈ 𝐾) → (∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 ↔ 𝑦 ∈ 𝑧) → ((𝐹‘𝑥) ∈ 𝑤 ↔ (𝐹‘𝑦) ∈ 𝑤)))
27	26	ralrimdva 3189	. . . . 5 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → (∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 ↔ 𝑦 ∈ 𝑧) → ∀𝑤 ∈ 𝐾 ((𝐹‘𝑥) ∈ 𝑤 ↔ (𝐹‘𝑦) ∈ 𝑤)))
28		simpl1 1187	. . . . . 6 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → 𝐾 ∈ Kol2)
29	15, 11	ffvelrnd 6852	. . . . . 6 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → (𝐹‘𝑥) ∈ ∪ 𝐾)
30	15, 20	ffvelrnd 6852	. . . . . 6 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → (𝐹‘𝑦) ∈ ∪ 𝐾)
31	13	t0sep 21932	. . . . . 6 ⊢ ((𝐾 ∈ Kol2 ∧ ((𝐹‘𝑥) ∈ ∪ 𝐾 ∧ (𝐹‘𝑦) ∈ ∪ 𝐾)) → (∀𝑤 ∈ 𝐾 ((𝐹‘𝑥) ∈ 𝑤 ↔ (𝐹‘𝑦) ∈ 𝑤) → (𝐹‘𝑥) = (𝐹‘𝑦)))
32	28, 29, 30, 31	syl12anc 834	. . . . 5 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → (∀𝑤 ∈ 𝐾 ((𝐹‘𝑥) ∈ 𝑤 ↔ (𝐹‘𝑦) ∈ 𝑤) → (𝐹‘𝑥) = (𝐹‘𝑦)))
33	27, 32	syld 47	. . . 4 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → (∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 ↔ 𝑦 ∈ 𝑧) → (𝐹‘𝑥) = (𝐹‘𝑦)))
34		simpl2 1188	. . . . 5 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → 𝐹:𝑋–1-1→𝑌)
35	15	fdmd 6523	. . . . . . 7 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → dom 𝐹 = ∪ 𝐽)
36		f1dm 6579	. . . . . . . 8 ⊢ (𝐹:𝑋–1-1→𝑌 → dom 𝐹 = 𝑋)
37	34, 36	syl 17	. . . . . . 7 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → dom 𝐹 = 𝑋)
38	35, 37	eqtr3d 2858	. . . . . 6 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → ∪ 𝐽 = 𝑋)
39	11, 38	eleqtrd 2915	. . . . 5 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → 𝑥 ∈ 𝑋)
40	20, 38	eleqtrd 2915	. . . . 5 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → 𝑦 ∈ 𝑋)
41		f1fveq 7020	. . . . 5 ⊢ ((𝐹:𝑋–1-1→𝑌 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝐹‘𝑥) = (𝐹‘𝑦) ↔ 𝑥 = 𝑦))
42	34, 39, 40, 41	syl12anc 834	. . . 4 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → ((𝐹‘𝑥) = (𝐹‘𝑦) ↔ 𝑥 = 𝑦))
43	33, 42	sylibd 241	. . 3 ⊢ (((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → (∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 ↔ 𝑦 ∈ 𝑧) → 𝑥 = 𝑦))
44	43	ralrimivva 3191	. 2 ⊢ ((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) → ∀𝑥 ∈ ∪ 𝐽∀𝑦 ∈ ∪ 𝐽(∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 ↔ 𝑦 ∈ 𝑧) → 𝑥 = 𝑦))
45	12	ist0 21928	. 2 ⊢ (𝐽 ∈ Kol2 ↔ (𝐽 ∈ Top ∧ ∀𝑥 ∈ ∪ 𝐽∀𝑦 ∈ ∪ 𝐽(∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 ↔ 𝑦 ∈ 𝑧) → 𝑥 = 𝑦)))
46	2, 44, 45	sylanbrc 585	1 ⊢ ((𝐾 ∈ Kol2 ∧ 𝐹:𝑋–1-1→𝑌 ∧ 𝐹 ∈ (𝐽 Cn 𝐾)) → 𝐽 ∈ Kol2)

Syntax hints:   → wi 4   ↔ wb 208   ∧ wa 398   ∧ w3a 1083   = wceq 1537   ∈ wcel 2114  ∀wral 3138  ∪ cuni 4838  ^◡ccnv 5554  dom cdm 5555   “ cima 5558   Fn wfn 6350  ⟶wf 6351  –1-1→wf1 6352  ‘cfv 6355  (class class class)co 7156  Topctop 21501   Cn ccn 21832  Kol2ct0 21914

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1970  ax-7 2015  ax-8 2116  ax-9 2124  ax-10 2145  ax-11 2161  ax-12 2177  ax-ext 2793  ax-sep 5203  ax-nul 5210  ax-pow 5266  ax-pr 5330  ax-un 7461

This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-3an 1085  df-tru 1540  df-ex 1781  df-nf 1785  df-sb 2070  df-mo 2622  df-eu 2654  df-clab 2800  df-cleq 2814  df-clel 2893  df-nfc 2963  df-ne 3017  df-ral 3143  df-rex 3144  df-rab 3147  df-v 3496  df-sbc 3773  df-dif 3939  df-un 3941  df-in 3943  df-ss 3952  df-nul 4292  df-if 4468  df-pw 4541  df-sn 4568  df-pr 4570  df-op 4574  df-uni 4839  df-br 5067  df-opab 5129  df-mpt 5147  df-id 5460  df-xp 5561  df-rel 5562  df-cnv 5563  df-co 5564  df-dm 5565  df-rn 5566  df-res 5567  df-ima 5568  df-iota 6314  df-fun 6357  df-fn 6358  df-f 6359  df-f1 6360  df-fv 6363  df-ov 7159  df-oprab 7160  df-mpo 7161  df-map 8408  df-top 21502  df-topon 21519  df-cn 21835  df-t0 21921

This theorem is referenced by:  restt0  21974  sst0  21981  t0hmph  22398