Theorem fbflim2 24302

Description: A condition for a filter base 𝐵 to converge to a point 𝐴. Use neighborhoods instead of open neighborhoods. Compare fbflim 24301. (Contributed by FL, 4-Jul-2011.) (Revised by Stefan O'Rear, 6-Aug-2015.)

Hypothesis

Ref	Expression
fbflim.3	⊢ 𝐹 = (𝑋filGen𝐵)

Assertion

Ref	Expression
fbflim2	⊢ ((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) → (𝐴 ∈ (𝐽 fLim 𝐹) ↔ (𝐴 ∈ 𝑋 ∧ ∀𝑛 ∈ ((nei‘𝐽)‘{𝐴})∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛)))

Distinct variable groups:   𝑥,𝑛,𝐴   𝐵,𝑛,𝑥   𝑛,𝐽,𝑥   𝑛,𝑋,𝑥   𝑥,𝐹

Allowed substitution hint:   𝐹(𝑛)

Proof of Theorem fbflim2

Dummy variable 𝑦 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		fbflim.3	. . 3 ⊢ 𝐹 = (𝑋filGen𝐵)
2	1	fbflim 24301	. 2 ⊢ ((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) → (𝐴 ∈ (𝐽 fLim 𝐹) ↔ (𝐴 ∈ 𝑋 ∧ ∀𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦))))
3		topontop 23237	. . . . . . . . 9 ⊢ (𝐽 ∈ (TopOn‘𝑋) → 𝐽 ∈ Top)
4	3	ad2antrr 739	. . . . . . . 8 ⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) → 𝐽 ∈ Top)
5		simpr 490	. . . . . . . . 9 ⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) → 𝐴 ∈ 𝑋)
6		toponuni 23238	. . . . . . . . . 10 ⊢ (𝐽 ∈ (TopOn‘𝑋) → 𝑋 = ∪ 𝐽)
7	6	ad2antrr 739	. . . . . . . . 9 ⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) → 𝑋 = ∪ 𝐽)
8	5, 7	eleqtrd 2862	. . . . . . . 8 ⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) → 𝐴 ∈ ∪ 𝐽)
9		eqid 2760	. . . . . . . . 9 ⊢ ∪ 𝐽 = ∪ 𝐽
10	9	isneip 23429	. . . . . . . 8 ⊢ ((𝐽 ∈ Top ∧ 𝐴 ∈ ∪ 𝐽) → (𝑛 ∈ ((nei‘𝐽)‘{𝐴}) ↔ (𝑛 ⊆ ∪ 𝐽 ∧ ∃𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 ∧ 𝑦 ⊆ 𝑛))))
11	4, 8, 10	syl2anc 596	. . . . . . 7 ⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) → (𝑛 ∈ ((nei‘𝐽)‘{𝐴}) ↔ (𝑛 ⊆ ∪ 𝐽 ∧ ∃𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 ∧ 𝑦 ⊆ 𝑛))))
12		simpr 490	. . . . . . 7 ⊢ ((𝑛 ⊆ ∪ 𝐽 ∧ ∃𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 ∧ 𝑦 ⊆ 𝑛)) → ∃𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 ∧ 𝑦 ⊆ 𝑛))
13	11, 12	biimtrdi 256	. . . . . 6 ⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) → (𝑛 ∈ ((nei‘𝐽)‘{𝐴}) → ∃𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 ∧ 𝑦 ⊆ 𝑛)))
14		r19.29 3125	. . . . . . . 8 ⊢ ((∀𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦) ∧ ∃𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 ∧ 𝑦 ⊆ 𝑛)) → ∃𝑦 ∈ 𝐽 ((𝐴 ∈ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦) ∧ (𝐴 ∈ 𝑦 ∧ 𝑦 ⊆ 𝑛)))
15		pm3.45 634	. . . . . . . . . . 11 ⊢ ((𝐴 ∈ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦) → ((𝐴 ∈ 𝑦 ∧ 𝑦 ⊆ 𝑛) → (∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦 ∧ 𝑦 ⊆ 𝑛)))
16	15	imp 412	. . . . . . . . . 10 ⊢ (((𝐴 ∈ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦) ∧ (𝐴 ∈ 𝑦 ∧ 𝑦 ⊆ 𝑛)) → (∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦 ∧ 𝑦 ⊆ 𝑛))
17		sstr2 3915	. . . . . . . . . . . . 13 ⊢ (𝑥 ⊆ 𝑦 → (𝑦 ⊆ 𝑛 → 𝑥 ⊆ 𝑛))
18	17	com12 33	. . . . . . . . . . . 12 ⊢ (𝑦 ⊆ 𝑛 → (𝑥 ⊆ 𝑦 → 𝑥 ⊆ 𝑛))
19	18	reximdv 3177	. . . . . . . . . . 11 ⊢ (𝑦 ⊆ 𝑛 → (∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛))
20	19	impcom 413	. . . . . . . . . 10 ⊢ ((∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦 ∧ 𝑦 ⊆ 𝑛) → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛)
21	16, 20	syl 18	. . . . . . . . 9 ⊢ (((𝐴 ∈ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦) ∧ (𝐴 ∈ 𝑦 ∧ 𝑦 ⊆ 𝑛)) → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛)
22	21	rexlimivw 3159	. . . . . . . 8 ⊢ (∃𝑦 ∈ 𝐽 ((𝐴 ∈ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦) ∧ (𝐴 ∈ 𝑦 ∧ 𝑦 ⊆ 𝑛)) → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛)
23	14, 22	syl 18	. . . . . . 7 ⊢ ((∀𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦) ∧ ∃𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 ∧ 𝑦 ⊆ 𝑛)) → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛)
24	23	ex 418	. . . . . 6 ⊢ (∀𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦) → (∃𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 ∧ 𝑦 ⊆ 𝑛) → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛))
25	13, 24	syl9 78	. . . . 5 ⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) → (∀𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦) → (𝑛 ∈ ((nei‘𝐽)‘{𝐴}) → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛)))
26	25	ralrimdv 3160	. . . 4 ⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) → (∀𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦) → ∀𝑛 ∈ ((nei‘𝐽)‘{𝐴})∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛))
27	4	adantr 486	. . . . . . . . 9 ⊢ ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) ∧ (𝑦 ∈ 𝐽 ∧ 𝐴 ∈ 𝑦)) → 𝐽 ∈ Top)
28		simprl 783	. . . . . . . . 9 ⊢ ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) ∧ (𝑦 ∈ 𝐽 ∧ 𝐴 ∈ 𝑦)) → 𝑦 ∈ 𝐽)
29		simprr 785	. . . . . . . . 9 ⊢ ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) ∧ (𝑦 ∈ 𝐽 ∧ 𝐴 ∈ 𝑦)) → 𝐴 ∈ 𝑦)
30		opnneip 23443	. . . . . . . . 9 ⊢ ((𝐽 ∈ Top ∧ 𝑦 ∈ 𝐽 ∧ 𝐴 ∈ 𝑦) → 𝑦 ∈ ((nei‘𝐽)‘{𝐴}))
31	27, 28, 29, 30	syl3anc 1398	. . . . . . . 8 ⊢ ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) ∧ (𝑦 ∈ 𝐽 ∧ 𝐴 ∈ 𝑦)) → 𝑦 ∈ ((nei‘𝐽)‘{𝐴}))
32		sseq2 3934	. . . . . . . . . 10 ⊢ (𝑛 = 𝑦 → (𝑥 ⊆ 𝑛 ↔ 𝑥 ⊆ 𝑦))
33	32	rexbidv 3186	. . . . . . . . 9 ⊢ (𝑛 = 𝑦 → (∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛 ↔ ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦))
34	33	rspcv 3572	. . . . . . . 8 ⊢ (𝑦 ∈ ((nei‘𝐽)‘{𝐴}) → (∀𝑛 ∈ ((nei‘𝐽)‘{𝐴})∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦))
35	31, 34	syl 18	. . . . . . 7 ⊢ ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) ∧ (𝑦 ∈ 𝐽 ∧ 𝐴 ∈ 𝑦)) → (∀𝑛 ∈ ((nei‘𝐽)‘{𝐴})∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦))
36	35	expr 462	. . . . . 6 ⊢ ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) ∧ 𝑦 ∈ 𝐽) → (𝐴 ∈ 𝑦 → (∀𝑛 ∈ ((nei‘𝐽)‘{𝐴})∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦)))
37	36	com23 87	. . . . 5 ⊢ ((((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) ∧ 𝑦 ∈ 𝐽) → (∀𝑛 ∈ ((nei‘𝐽)‘{𝐴})∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛 → (𝐴 ∈ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦)))
38	37	ralrimdva 3162	. . . 4 ⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) → (∀𝑛 ∈ ((nei‘𝐽)‘{𝐴})∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛 → ∀𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦)))
39	26, 38	impbid 215	. . 3 ⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) ∧ 𝐴 ∈ 𝑋) → (∀𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦) ↔ ∀𝑛 ∈ ((nei‘𝐽)‘{𝐴})∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛))
40	39	pm5.32da 590	. 2 ⊢ ((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) → ((𝐴 ∈ 𝑋 ∧ ∀𝑦 ∈ 𝐽 (𝐴 ∈ 𝑦 → ∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑦)) ↔ (𝐴 ∈ 𝑋 ∧ ∀𝑛 ∈ ((nei‘𝐽)‘{𝐴})∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛)))
41	2, 40	bitrd 282	1 ⊢ ((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐵 ∈ (fBas‘𝑋)) → (𝐴 ∈ (𝐽 fLim 𝐹) ↔ (𝐴 ∈ 𝑋 ∧ ∀𝑛 ∈ ((nei‘𝐽)‘{𝐴})∃𝑥 ∈ 𝐵 𝑥 ⊆ 𝑛)))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   = wceq 1569   ∈ wcel 2144  ∀wral 3076  ∃wrex 3086   ⊆ wss 3895  {csn 4584  ∪ cuni 4866  ‘cfv 6539  (class class class)co 7421  fBascfbas 21672  filGencfg 21673  Topctop 23217  TopOnctopon 23234  neicnei 23421   fLim cflim 24259

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1827  ax-4 1841  ax-5 1942  ax-6 1999  ax-7 2040  ax-8 2146  ax-9 2154  ax-10 2177  ax-11 2193  ax-12 2212  ax-ext 2732  ax-rep 5231  ax-sep 5248  ax-nul 5259  ax-pow 5326  ax-pr 5390  ax-un 7752

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1572  df-fal 1582  df-ex 1812  df-nf 1816  df-sb 2099  df-mo 2564  df-eu 2594  df-clab 2739  df-cleq 2752  df-clel 2835  df-nfc 2909  df-ne 2956  df-nel 3062  df-ral 3077  df-rex 3087  df-reu 3366  df-rab 3413  df-v 3452  df-sbc 3739  df-csb 3847  df-ss 3896  df-dif 4047  df-in 4091  df-un 4151  df-nul 4279  df-if 4482  df-pw 4558  df-sn 4585  df-pr 4587  df-op 4835  df-uni 4867  df-iun 4952  df-br 5103  df-opab 5167  df-mpt 5186  df-id 5545  df-xp 5656  df-rel 5657  df-cnv 5658  df-co 5659  df-dm 5660  df-rn 5661  df-res 5662  df-ima 5663  df-iota 6494  df-fun 6541  df-fn 6542  df-f 6543  df-f1 6544  df-fo 6545  df-f1o 6546  df-fv 6547  df-ov 7424  df-oprab 7425  df-mpo 7426  df-fbas 21681  df-fg 21682  df-top 23218  df-topon 23235  df-ntr 23344  df-nei 23422  df-fil 24171  df-flim 24264

This theorem is used by: (None)