Theorem climuz 42045

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 42044	. 2 ⊢ (𝜑 → (𝐹 ⇝ 𝐴 ↔ (𝐴 ∈ ℂ ∧ ∀𝑦 ∈ ℝ+ ∃𝑖 ∈ 𝑍 ∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑦)))
5		breq2 5070	. . . . . . . 8 ⊢ (𝑦 = 𝑥 → ((abs‘((𝐹‘𝑙) − 𝐴)) < 𝑦 ↔ (abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥))
6	5	ralbidv 3197	. . . . . . 7 ⊢ (𝑦 = 𝑥 → (∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑦 ↔ ∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥))
7	6	rexbidv 3297	. . . . . 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 6670	. . . . . . . . . 10 ⊢ (𝑖 = 𝑗 → (ℤ≥‘𝑖) = (ℤ≥‘𝑗))
9	8	raleqdv 3415	. . . . . . . . 9 ⊢ (𝑖 = 𝑗 → (∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥 ↔ ∀𝑙 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥))
10		nfcv 2977	. . . . . . . . . . . . 13 ⊢ Ⅎ𝑘abs
11		climuz.k	. . . . . . . . . . . . . . 15 ⊢ Ⅎ𝑘𝐹
12		nfcv 2977	. . . . . . . . . . . . . . 15 ⊢ Ⅎ𝑘𝑙
13	11, 12	nffv 6680	. . . . . . . . . . . . . 14 ⊢ Ⅎ𝑘(𝐹‘𝑙)
14		nfcv 2977	. . . . . . . . . . . . . 14 ⊢ Ⅎ𝑘 −
15		nfcv 2977	. . . . . . . . . . . . . 14 ⊢ Ⅎ𝑘𝐴
16	13, 14, 15	nfov 7186	. . . . . . . . . . . . 13 ⊢ Ⅎ𝑘((𝐹‘𝑙) − 𝐴)
17	10, 16	nffv 6680	. . . . . . . . . . . 12 ⊢ Ⅎ𝑘(abs‘((𝐹‘𝑙) − 𝐴))
18		nfcv 2977	. . . . . . . . . . . 12 ⊢ Ⅎ𝑘 <
19		nfcv 2977	. . . . . . . . . . . 12 ⊢ Ⅎ𝑘𝑥
20	17, 18, 19	nfbr 5113	. . . . . . . . . . 11 ⊢ Ⅎ𝑘(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥
21		nfv 1915	. . . . . . . . . . 11 ⊢ Ⅎ𝑙(abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥
22		fveq2 6670	. . . . . . . . . . . . 13 ⊢ (𝑙 = 𝑘 → (𝐹‘𝑙) = (𝐹‘𝑘))
23	22	fvoveq1d 7178	. . . . . . . . . . . 12 ⊢ (𝑙 = 𝑘 → (abs‘((𝐹‘𝑙) − 𝐴)) = (abs‘((𝐹‘𝑘) − 𝐴)))
24	23	breq1d 5076	. . . . . . . . . . 11 ⊢ (𝑙 = 𝑘 → ((abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥 ↔ (abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥))
25	20, 21, 24	cbvralw 3441	. . . . . . . . . 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 281	. . . . . . . 8 ⊢ (𝑖 = 𝑗 → (∀𝑙 ∈ (ℤ≥‘𝑖)(abs‘((𝐹‘𝑙) − 𝐴)) < 𝑥 ↔ ∀𝑘 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥))
28	27	cbvrexvw 3450	. . . . . . 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 281	. . . . 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 3449	. . . 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 624	. . 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 281	1 ⊢ (𝜑 → (𝐹 ⇝ 𝐴 ↔ (𝐴 ∈ ℂ ∧ ∀𝑥 ∈ ℝ+ ∃𝑗 ∈ 𝑍 ∀𝑘 ∈ (ℤ≥‘𝑗)(abs‘((𝐹‘𝑘) − 𝐴)) < 𝑥)))

Syntax hints:   → wi 4   ↔ wb 208   ∧ wa 398   = wceq 1537   ∈ wcel 2114  Ⅎwnfc 2961  ∀wral 3138  ∃wrex 3139   class class class wbr 5066  ⟶wf 6351  ‘cfv 6355  (class class class)co 7156  ℂcc 10535   < clt 10675   − cmin 10870  ℤcz 11982  ℤ_≥cuz 12244  ℝ⁺crp 12390  abscabs 14593   ⇝ cli 14841

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-rep 5190  ax-sep 5203  ax-nul 5210  ax-pow 5266  ax-pr 5330  ax-un 7461  ax-cnex 10593  ax-resscn 10594  ax-pre-lttri 10611  ax-pre-lttrn 10612

This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-3or 1084  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-nel 3124  df-ral 3143  df-rex 3144  df-reu 3145  df-rab 3147  df-v 3496  df-sbc 3773  df-csb 3884  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-iun 4921  df-br 5067  df-opab 5129  df-mpt 5147  df-id 5460  df-po 5474  df-so 5475  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-fo 6361  df-f1o 6362  df-fv 6363  df-ov 7159  df-er 8289  df-en 8510  df-dom 8511  df-sdom 8512  df-pnf 10677  df-mnf 10678  df-xr 10679  df-ltxr 10680  df-le 10681  df-neg 10873  df-z 11983  df-uz 12245  df-clim 14845

This theorem is referenced by:  liminflimsupclim  42108  climxlim2lem  42146