Theorem climuz 42867

Description: Express the predicate: The limit of complex number sequence 𝐹 is 𝐴, or 𝐹 converges to 𝐴. (Contributed by Glauco Siliprandi, 2-Jan-2022.)

Hypotheses

Ref	Expression
climuz.k	⊢ Ⅎ𝑘𝐹
climuz.m	⊢ (𝜑 → 𝑀 ∈ ℤ)
climuz.z	⊢ 𝑍 = (ℤ≥‘𝑀)
climuz.f	⊢ (𝜑 → 𝐹:𝑍⟶ℂ)

Assertion

Ref	Expression
climuz	⊢ (𝜑 → (𝐹 ⇝ 𝐴 ↔ (𝐴 ∈ ℂ ∧ ∀𝑥 ∈ ℝ+ ∃𝑗 ∈ 𝑍 ∀𝑘 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥)))

Distinct variable groups:   𝐴,𝑗,𝑘,𝑥   𝑗,𝐹,𝑥   𝑗,𝑍,𝑥

Allowed substitution hints:   𝜑(𝑥,𝑗,𝑘)   𝐹(𝑘)   𝑀(𝑥,𝑗,𝑘)   𝑍(𝑘)

Proof of Theorem climuz

Dummy variables 𝑖 𝑙 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		climuz.m	. . 3 ⊢ (𝜑 → 𝑀 ∈ ℤ)
2		climuz.z	. . 3 ⊢ 𝑍 = (ℤ≥‘𝑀)
3		climuz.f	. . 3 ⊢ (𝜑 → 𝐹:𝑍⟶ℂ)
4	1, 2, 3	climuzlem 42866	. 2 ⊢ (𝜑 → (𝐹 ⇝ 𝐴 ↔ (𝐴 ∈ ℂ ∧ ∀𝑦 ∈ ℝ+ ∃𝑖 ∈ 𝑍 ∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑦)))
5		breq2 5044	. . . . . . . 8 ⊢ (𝑦 = 𝑥 → ((abs‘((𝐹‘𝑙) − 𝐴)) < 𝑦 ↔ (abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥))
6	5	ralbidv 3110	. . . . . . 7 ⊢ (𝑦 = 𝑥 → (∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑦 ↔ ∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥))
7	6	rexbidv 3208	. . . . . 6 ⊢ (𝑦 = 𝑥 → (∃𝑖 ∈ 𝑍 ∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑦 ↔ ∃𝑖 ∈ 𝑍 ∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥))
8		fveq2 6686	. . . . . . . . . 10 ⊢ (𝑖 = 𝑗 → (ℤ≥‘𝑖) = (ℤ≥‘𝑗))
9	8	raleqdv 3317	. . . . . . . . 9 ⊢ (𝑖 = 𝑗 → (∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥 ↔ ∀𝑙 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥))
10		nfcv 2900	. . . . . . . . . . . . 13 ⊢ Ⅎ𝑘abs
11		climuz.k	. . . . . . . . . . . . . . 15 ⊢ Ⅎ𝑘𝐹
12		nfcv 2900	. . . . . . . . . . . . . . 15 ⊢ Ⅎ𝑘𝑙
13	11, 12	nffv 6696	. . . . . . . . . . . . . 14 ⊢ Ⅎ𝑘(𝐹‘𝑙)
14		nfcv 2900	. . . . . . . . . . . . . 14 ⊢ Ⅎ𝑘 −
15		nfcv 2900	. . . . . . . . . . . . . 14 ⊢ Ⅎ𝑘𝐴
16	13, 14, 15	nfov 7212	. . . . . . . . . . . . 13 ⊢ Ⅎ𝑘((𝐹‘𝑙) − 𝐴)
17	10, 16	nffv 6696	. . . . . . . . . . . 12 ⊢ Ⅎ𝑘(abs‘((𝐹‘𝑙) − 𝐴))
18		nfcv 2900	. . . . . . . . . . . 12 ⊢ Ⅎ𝑘 <
19		nfcv 2900	. . . . . . . . . . . 12 ⊢ Ⅎ𝑘𝑥
20	17, 18, 19	nfbr 5087	. . . . . . . . . . 11 ⊢ Ⅎ𝑘(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥
21		nfv 1921	. . . . . . . . . . 11 ⊢ Ⅎ𝑙(abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥
22		fveq2 6686	. . . . . . . . . . . . 13 ⊢ (𝑙 = 𝑘 → (𝐹‘𝑙) = (𝐹‘𝑘))
23	22	fvoveq1d 7204	. . . . . . . . . . . 12 ⊢ (𝑙 = 𝑘 → (abs‘((𝐹‘𝑙) − 𝐴)) = (abs‘((𝐹‘𝑘) − 𝐴)))
24	23	breq1d 5050	. . . . . . . . . . 11 ⊢ (𝑙 = 𝑘 → ((abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥 ↔ (abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥))
25	20, 21, 24	cbvralw 3341	. . . . . . . . . 10 ⊢ (∀𝑙 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥 ↔ ∀𝑘 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥)
26	25	a1i 11	. . . . . . . . 9 ⊢ (𝑖 = 𝑗 → (∀𝑙 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥 ↔ ∀𝑘 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥))
27	9, 26	bitrd 282	. . . . . . . 8 ⊢ (𝑖 = 𝑗 → (∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥 ↔ ∀𝑘 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥))
28	27	cbvrexvw 3351	. . . . . . 7 ⊢ (∃𝑖 ∈ 𝑍 ∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥 ↔ ∃𝑗 ∈ 𝑍 ∀𝑘 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥)
29	28	a1i 11	. . . . . 6 ⊢ (𝑦 = 𝑥 → (∃𝑖 ∈ 𝑍 ∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥 ↔ ∃𝑗 ∈ 𝑍 ∀𝑘 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥))
30	7, 29	bitrd 282	. . . . 5 ⊢ (𝑦 = 𝑥 → (∃𝑖 ∈ 𝑍 ∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑦 ↔ ∃𝑗 ∈ 𝑍 ∀𝑘 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥))
31	30	cbvralvw 3350	. . . 4 ⊢ (∀𝑦 ∈ ℝ+ ∃𝑖 ∈ 𝑍 ∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑦 ↔ ∀𝑥 ∈ ℝ+ ∃𝑗 ∈ 𝑍 ∀𝑘 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥)
32	31	anbi2i 626	. . 3 ⊢ ((𝐴 ∈ ℂ ∧ ∀𝑦 ∈ ℝ+ ∃𝑖 ∈ 𝑍 ∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑦) ↔ (𝐴 ∈ ℂ ∧ ∀𝑥 ∈ ℝ+ ∃𝑗 ∈ 𝑍 ∀𝑘 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥))
33	32	a1i 11	. 2 ⊢ (𝜑 → ((𝐴 ∈ ℂ ∧ ∀𝑦 ∈ ℝ+ ∃𝑖 ∈ 𝑍 ∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑦) ↔ (𝐴 ∈ ℂ ∧ ∀𝑥 ∈ ℝ+ ∃𝑗 ∈ 𝑍 ∀𝑘 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥)))
34	4, 33	bitrd 282	1 ⊢ (𝜑 → (𝐹 ⇝ 𝐴 ↔ (𝐴 ∈ ℂ ∧ ∀𝑥 ∈ ℝ+ ∃𝑗 ∈ 𝑍 ∀𝑘 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥)))

Syntax hints:   → wi 4   ↔ wb 209   ∧ wa 399   = wceq 1542   ∈ wcel 2114  Ⅎwnfc 2880  ∀wral 3054  ∃wrex 3055   class class class wbr 5040  ⟶wf 6345  ‘cfv 6349  (class class class)co 7182  ℂcc 10625   < clt 10765   − cmin 10960  ℤcz 12074  ℤ_≥cuz 12336  ℝ⁺crp 12484  abscabs 14695   ⇝ cli 14943

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1802  ax-4 1816  ax-5 1917  ax-6 1975  ax-7 2020  ax-8 2116  ax-9 2124  ax-10 2145  ax-11 2162  ax-12 2179  ax-ext 2711  ax-rep 5164  ax-sep 5177  ax-nul 5184  ax-pow 5242  ax-pr 5306  ax-un 7491  ax-cnex 10683  ax-resscn 10684  ax-pre-lttri 10701  ax-pre-lttrn 10702

This theorem depends on definitions:  df-bi 210  df-an 400  df-or 847  df-3or 1089  df-3an 1090  df-tru 1545  df-fal 1555  df-ex 1787  df-nf 1791  df-sb 2075  df-mo 2541  df-eu 2571  df-clab 2718  df-cleq 2731  df-clel 2812  df-nfc 2882  df-ne 2936  df-nel 3040  df-ral 3059  df-rex 3060  df-reu 3061  df-rab 3063  df-v 3402  df-sbc 3686  df-csb 3801  df-dif 3856  df-un 3858  df-in 3860  df-ss 3870  df-nul 4222  df-if 4425  df-pw 4500  df-sn 4527  df-pr 4529  df-op 4533  df-uni 4807  df-iun 4893  df-br 5041  df-opab 5103  df-mpt 5121  df-id 5439  df-po 5452  df-so 5453  df-xp 5541  df-rel 5542  df-cnv 5543  df-co 5544  df-dm 5545  df-rn 5546  df-res 5547  df-ima 5548  df-iota 6307  df-fun 6351  df-fn 6352  df-f 6353  df-f1 6354  df-fo 6355  df-f1o 6356  df-fv 6357  df-ov 7185  df-er 8332  df-en 8568  df-dom 8569  df-sdom 8570  df-pnf 10767  df-mnf 10768  df-xr 10769  df-ltxr 10770  df-le 10771  df-neg 10963  df-z 12075  df-uz 12337  df-clim 14947

This theorem is referenced by:  liminflimsupclim  42930  climxlim2lem  42968