Theorem haust1 23414

Description: A Hausdorff space is a T₁ space. (Contributed by FL, 11-Jun-2007.) (Proof shortened by Mario Carneiro, 24-Aug-2015.)

Assertion

Ref	Expression
haust1	⊢ (𝐽 ∈ Haus → 𝐽 ∈ Fre)

Proof of Theorem haust1

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

Step	Hyp	Ref	Expression
1		eqid 2764	. . . . . . . . 9 ⊢ ∪ 𝐽 = ∪ 𝐽
2	1	hausnei 23390	. . . . . . . 8 ⊢ ((𝐽 ∈ Haus ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽 ∧ 𝑥 ≠ 𝑦)) → ∃𝑧 ∈ 𝐽 ∃𝑤 ∈ 𝐽 (𝑥 ∈ 𝑧 ∧ 𝑦 ∈ 𝑤 ∧ (𝑧 ∩ 𝑤) = ∅))
3		simprr1 1236	. . . . . . . . . . 11 ⊢ ((((𝐽 ∈ Haus ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽 ∧ 𝑥 ≠ 𝑦)) ∧ 𝑧 ∈ 𝐽) ∧ (𝑤 ∈ 𝐽 ∧ (𝑥 ∈ 𝑧 ∧ 𝑦 ∈ 𝑤 ∧ (𝑧 ∩ 𝑤) = ∅))) → 𝑥 ∈ 𝑧)
4		noel 4292	. . . . . . . . . . . . 13 ⊢ ¬ 𝑦 ∈ ∅
5		simprr3 1238	. . . . . . . . . . . . . 14 ⊢ ((((𝐽 ∈ Haus ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽 ∧ 𝑥 ≠ 𝑦)) ∧ 𝑧 ∈ 𝐽) ∧ (𝑤 ∈ 𝐽 ∧ (𝑥 ∈ 𝑧 ∧ 𝑦 ∈ 𝑤 ∧ (𝑧 ∩ 𝑤) = ∅))) → (𝑧 ∩ 𝑤) = ∅)
6	5	eleq2d 2850	. . . . . . . . . . . . 13 ⊢ ((((𝐽 ∈ Haus ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽 ∧ 𝑥 ≠ 𝑦)) ∧ 𝑧 ∈ 𝐽) ∧ (𝑤 ∈ 𝐽 ∧ (𝑥 ∈ 𝑧 ∧ 𝑦 ∈ 𝑤 ∧ (𝑧 ∩ 𝑤) = ∅))) → (𝑦 ∈ (𝑧 ∩ 𝑤) ↔ 𝑦 ∈ ∅))
7	4, 6	mtbiri 329	. . . . . . . . . . . 12 ⊢ ((((𝐽 ∈ Haus ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽 ∧ 𝑥 ≠ 𝑦)) ∧ 𝑧 ∈ 𝐽) ∧ (𝑤 ∈ 𝐽 ∧ (𝑥 ∈ 𝑧 ∧ 𝑦 ∈ 𝑤 ∧ (𝑧 ∩ 𝑤) = ∅))) → ¬ 𝑦 ∈ (𝑧 ∩ 𝑤))
8		simprr2 1237	. . . . . . . . . . . . 13 ⊢ ((((𝐽 ∈ Haus ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽 ∧ 𝑥 ≠ 𝑦)) ∧ 𝑧 ∈ 𝐽) ∧ (𝑤 ∈ 𝐽 ∧ (𝑥 ∈ 𝑧 ∧ 𝑦 ∈ 𝑤 ∧ (𝑧 ∩ 𝑤) = ∅))) → 𝑦 ∈ 𝑤)
9		elin 3922	. . . . . . . . . . . . . 14 ⊢ (𝑦 ∈ (𝑧 ∩ 𝑤) ↔ (𝑦 ∈ 𝑧 ∧ 𝑦 ∈ 𝑤))
10	9	simplbi2com 506	. . . . . . . . . . . . 13 ⊢ (𝑦 ∈ 𝑤 → (𝑦 ∈ 𝑧 → 𝑦 ∈ (𝑧 ∩ 𝑤)))
11	8, 10	syl 17	. . . . . . . . . . . 12 ⊢ ((((𝐽 ∈ Haus ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽 ∧ 𝑥 ≠ 𝑦)) ∧ 𝑧 ∈ 𝐽) ∧ (𝑤 ∈ 𝐽 ∧ (𝑥 ∈ 𝑧 ∧ 𝑦 ∈ 𝑤 ∧ (𝑧 ∩ 𝑤) = ∅))) → (𝑦 ∈ 𝑧 → 𝑦 ∈ (𝑧 ∩ 𝑤)))
12	7, 11	mtod 200	. . . . . . . . . . 11 ⊢ ((((𝐽 ∈ Haus ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽 ∧ 𝑥 ≠ 𝑦)) ∧ 𝑧 ∈ 𝐽) ∧ (𝑤 ∈ 𝐽 ∧ (𝑥 ∈ 𝑧 ∧ 𝑦 ∈ 𝑤 ∧ (𝑧 ∩ 𝑤) = ∅))) → ¬ 𝑦 ∈ 𝑧)
13	3, 12	jca 519	. . . . . . . . . 10 ⊢ ((((𝐽 ∈ Haus ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽 ∧ 𝑥 ≠ 𝑦)) ∧ 𝑧 ∈ 𝐽) ∧ (𝑤 ∈ 𝐽 ∧ (𝑥 ∈ 𝑧 ∧ 𝑦 ∈ 𝑤 ∧ (𝑧 ∩ 𝑤) = ∅))) → (𝑥 ∈ 𝑧 ∧ ¬ 𝑦 ∈ 𝑧))
14	13	rexlimdvaa 3166	. . . . . . . . 9 ⊢ (((𝐽 ∈ Haus ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽 ∧ 𝑥 ≠ 𝑦)) ∧ 𝑧 ∈ 𝐽) → (∃𝑤 ∈ 𝐽 (𝑥 ∈ 𝑧 ∧ 𝑦 ∈ 𝑤 ∧ (𝑧 ∩ 𝑤) = ∅) → (𝑥 ∈ 𝑧 ∧ ¬ 𝑦 ∈ 𝑧)))
15	14	reximdva 3177	. . . . . . . 8 ⊢ ((𝐽 ∈ Haus ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽 ∧ 𝑥 ≠ 𝑦)) → (∃𝑧 ∈ 𝐽 ∃𝑤 ∈ 𝐽 (𝑥 ∈ 𝑧 ∧ 𝑦 ∈ 𝑤 ∧ (𝑧 ∩ 𝑤) = ∅) → ∃𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 ∧ ¬ 𝑦 ∈ 𝑧)))
16	2, 15	mpd 15	. . . . . . 7 ⊢ ((𝐽 ∈ Haus ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽 ∧ 𝑥 ≠ 𝑦)) → ∃𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 ∧ ¬ 𝑦 ∈ 𝑧))
17		rexanali 3118	. . . . . . 7 ⊢ (∃𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 ∧ ¬ 𝑦 ∈ 𝑧) ↔ ¬ ∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 → 𝑦 ∈ 𝑧))
18	16, 17	sylib 220	. . . . . 6 ⊢ ((𝐽 ∈ Haus ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽 ∧ 𝑥 ≠ 𝑦)) → ¬ ∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 → 𝑦 ∈ 𝑧))
19	18	3exp2 1369	. . . . 5 ⊢ (𝐽 ∈ Haus → (𝑥 ∈ ∪ 𝐽 → (𝑦 ∈ ∪ 𝐽 → (𝑥 ≠ 𝑦 → ¬ ∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 → 𝑦 ∈ 𝑧)))))
20	19	imp32 422	. . . 4 ⊢ ((𝐽 ∈ Haus ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → (𝑥 ≠ 𝑦 → ¬ ∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 → 𝑦 ∈ 𝑧)))
21	20	necon4ad 2978	. . 3 ⊢ ((𝐽 ∈ Haus ∧ (𝑥 ∈ ∪ 𝐽 ∧ 𝑦 ∈ ∪ 𝐽)) → (∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 → 𝑦 ∈ 𝑧) → 𝑥 = 𝑦))
22	21	ralrimivva 3207	. 2 ⊢ (𝐽 ∈ Haus → ∀𝑥 ∈ ∪ 𝐽∀𝑦 ∈ ∪ 𝐽(∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 → 𝑦 ∈ 𝑧) → 𝑥 = 𝑦))
23		haustop 23393	. . . 4 ⊢ (𝐽 ∈ Haus → 𝐽 ∈ Top)
24		toptopon2 22980	. . . 4 ⊢ (𝐽 ∈ Top ↔ 𝐽 ∈ (TopOn‘∪ 𝐽))
25	23, 24	sylib 220	. . 3 ⊢ (𝐽 ∈ Haus → 𝐽 ∈ (TopOn‘∪ 𝐽))
26		ist1-2 23409	. . 3 ⊢ (𝐽 ∈ (TopOn‘∪ 𝐽) → (𝐽 ∈ Fre ↔ ∀𝑥 ∈ ∪ 𝐽∀𝑦 ∈ ∪ 𝐽(∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 → 𝑦 ∈ 𝑧) → 𝑥 = 𝑦)))
27	25, 26	syl 17	. 2 ⊢ (𝐽 ∈ Haus → (𝐽 ∈ Fre ↔ ∀𝑥 ∈ ∪ 𝐽∀𝑦 ∈ ∪ 𝐽(∀𝑧 ∈ 𝐽 (𝑥 ∈ 𝑧 → 𝑦 ∈ 𝑧) → 𝑥 = 𝑦)))
28	22, 27	mpbird 259	1 ⊢ (𝐽 ∈ Haus → 𝐽 ∈ Fre)

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 208   ∧ wa 399   ∧ w3a 1099   = wceq 1562   ∈ wcel 2144   ≠ wne 2959  ∀wral 3078  ∃wrex 3088   ∩ cin 3905  ∅c0 4287  ∪ cuni 4867  ‘cfv 6523  Topctop 22955  TopOnctopon 22972  Frect1 23369  Hauscha 23370

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1817  ax-4 1831  ax-5 1932  ax-6 1989  ax-7 2030  ax-8 2146  ax-9 2154  ax-10 2177  ax-11 2193  ax-12 2214  ax-ext 2736  ax-sep 5248  ax-nul 5258  ax-pow 5324  ax-pr 5392  ax-un 7720

This theorem depends on definitions:  df-bi 209  df-an 400  df-or 859  df-3an 1101  df-tru 1565  df-fal 1575  df-ex 1802  df-nf 1806  df-sb 2093  df-mo 2568  df-eu 2598  df-clab 2743  df-cleq 2756  df-clel 2839  df-nfc 2913  df-ne 2960  df-ral 3079  df-rex 3089  df-rab 3417  df-v 3458  df-dif 3909  df-un 3911  df-in 3913  df-ss 3923  df-nul 4288  df-if 4483  df-pw 4559  df-sn 4585  df-pr 4587  df-op 4591  df-uni 4868  df-br 5103  df-opab 5165  df-mpt 5184  df-id 5544  df-xp 5655  df-rel 5656  df-cnv 5657  df-co 5658  df-dm 5659  df-iota 6479  df-fun 6525  df-fv 6531  df-topgen 17474  df-top 22956  df-topon 22973  df-cld 23081  df-t1 23376  df-haus 23377

This theorem is referenced by:  sncld  23433  ishaus3  23885  reghaus  23887  nrmhaus  23888  tgpt1  24180  metreg  24926  ipasslem8  31042  sitmcl  34650  onint1  36814  oninhaus  36815  poimirlem30  38154