geo2lim - Intuitionistic Logic Explorer

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Theorem geo2lim 12100

Description: The value of the infinite geometric series 2↑-1 + 2↑-2 +... , multiplied by a constant. (Contributed by Mario Carneiro, 15-Jun-2014.)

**Hypothesis**
Ref	Expression
geo2lim.1	⊢ 𝐹 = (𝑘 ∈ ℕ ↦ (𝐴 / (2↑𝑘)))

**Assertion**
Ref	Expression
geo2lim	⊢ (𝐴 ∈ ℂ → seq1( + , 𝐹) ⇝ 𝐴)

Distinct variable group: 𝐴,𝑘 Allowed substitution hint: 𝐹(𝑘)

Proof of Theorem geo2lim Dummy variables 𝑗 𝑛 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		nnuz 9797	. . 3 ⊢ ℕ = (ℤ_≥‘1)
2		1zzd 9511	. . 3 ⊢ (𝐴 ∈ ℂ → 1 ∈ ℤ)
3		halfcn 9363	. . . . . . 7 ⊢ (1 / 2) ∈ ℂ
4	3	a1i 9	. . . . . 6 ⊢ (𝐴 ∈ ℂ → (1 / 2) ∈ ℂ)
5		halfre 9362	. . . . . . . . 9 ⊢ (1 / 2) ∈ ℝ
6		halfge0 9365	. . . . . . . . 9 ⊢ 0 ≤ (1 / 2)
7		absid 11654	. . . . . . . . 9 ⊢ (((1 / 2) ∈ ℝ ∧ 0 ≤ (1 / 2)) → (abs‘(1 / 2)) = (1 / 2))
8	5, 6, 7	mp2an 426	. . . . . . . 8 ⊢ (abs‘(1 / 2)) = (1 / 2)
9		halflt1 9366	. . . . . . . 8 ⊢ (1 / 2) < 1
10	8, 9	eqbrtri 4110	. . . . . . 7 ⊢ (abs‘(1 / 2)) < 1
11	10	a1i 9	. . . . . 6 ⊢ (𝐴 ∈ ℂ → (abs‘(1 / 2)) < 1)
12	4, 11	expcnv 12088	. . . . 5 ⊢ (𝐴 ∈ ℂ → (𝑘 ∈ ℕ₀ ↦ ((1 / 2)↑𝑘)) ⇝ 0)
13		id 19	. . . . 5 ⊢ (𝐴 ∈ ℂ → 𝐴 ∈ ℂ)
14		geo2lim.1	. . . . . . 7 ⊢ 𝐹 = (𝑘 ∈ ℕ ↦ (𝐴 / (2↑𝑘)))
15		nnex 9154	. . . . . . . 8 ⊢ ℕ ∈ V
16	15	mptex 5885	. . . . . . 7 ⊢ (𝑘 ∈ ℕ ↦ (𝐴 / (2↑𝑘))) ∈ V
17	14, 16	eqeltri 2303	. . . . . 6 ⊢ 𝐹 ∈ V
18	17	a1i 9	. . . . 5 ⊢ (𝐴 ∈ ℂ → 𝐹 ∈ V)
19		nnnn0 9414	. . . . . . . 8 ⊢ (𝑗 ∈ ℕ → 𝑗 ∈ ℕ₀)
20	19	adantl 277	. . . . . . 7 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → 𝑗 ∈ ℕ₀)
21	3	a1i 9	. . . . . . . 8 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → (1 / 2) ∈ ℂ)
22	21, 20	expcld 10941	. . . . . . 7 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → ((1 / 2)↑𝑗) ∈ ℂ)
23		oveq2 6031	. . . . . . . 8 ⊢ (𝑘 = 𝑗 → ((1 / 2)↑𝑘) = ((1 / 2)↑𝑗))
24		eqid 2230	. . . . . . . 8 ⊢ (𝑘 ∈ ℕ₀ ↦ ((1 / 2)↑𝑘)) = (𝑘 ∈ ℕ₀ ↦ ((1 / 2)↑𝑘))
25	23, 24	fvmptg 5725	. . . . . . 7 ⊢ ((𝑗 ∈ ℕ₀ ∧ ((1 / 2)↑𝑗) ∈ ℂ) → ((𝑘 ∈ ℕ₀ ↦ ((1 / 2)↑𝑘))‘𝑗) = ((1 / 2)↑𝑗))
26	20, 22, 25	syl2anc 411	. . . . . 6 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → ((𝑘 ∈ ℕ₀ ↦ ((1 / 2)↑𝑘))‘𝑗) = ((1 / 2)↑𝑗))
27	26, 22	eqeltrd 2307	. . . . 5 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → ((𝑘 ∈ ℕ₀ ↦ ((1 / 2)↑𝑘))‘𝑗) ∈ ℂ)
28		simpl 109	. . . . . . 7 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → 𝐴 ∈ ℂ)
29		2nn 9310	. . . . . . . . 9 ⊢ 2 ∈ ℕ
30		nnexpcl 10820	. . . . . . . . 9 ⊢ ((2 ∈ ℕ ∧ 𝑗 ∈ ℕ₀) → (2↑𝑗) ∈ ℕ)
31	29, 20, 30	sylancr 414	. . . . . . . 8 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → (2↑𝑗) ∈ ℕ)
32	31	nncnd 9162	. . . . . . 7 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → (2↑𝑗) ∈ ℂ)
33	31	nnap0d 9194	. . . . . . 7 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → (2↑𝑗) # 0)
34	28, 32, 33	divrecapd 8978	. . . . . 6 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → (𝐴 / (2↑𝑗)) = (𝐴 · (1 / (2↑𝑗))))
35		simpr 110	. . . . . . 7 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → 𝑗 ∈ ℕ)
36	28, 32, 33	divclapd 8975	. . . . . . 7 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → (𝐴 / (2↑𝑗)) ∈ ℂ)
37		oveq2 6031	. . . . . . . . 9 ⊢ (𝑘 = 𝑗 → (2↑𝑘) = (2↑𝑗))
38	37	oveq2d 6039	. . . . . . . 8 ⊢ (𝑘 = 𝑗 → (𝐴 / (2↑𝑘)) = (𝐴 / (2↑𝑗)))
39	38, 14	fvmptg 5725	. . . . . . 7 ⊢ ((𝑗 ∈ ℕ ∧ (𝐴 / (2↑𝑗)) ∈ ℂ) → (𝐹‘𝑗) = (𝐴 / (2↑𝑗)))
40	35, 36, 39	syl2anc 411	. . . . . 6 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → (𝐹‘𝑗) = (𝐴 / (2↑𝑗)))
41		2cn 9219	. . . . . . . . 9 ⊢ 2 ∈ ℂ
42		2ap0 9241	. . . . . . . . 9 ⊢ 2 # 0
43		nnz 9503	. . . . . . . . . 10 ⊢ (𝑗 ∈ ℕ → 𝑗 ∈ ℤ)
44	43	adantl 277	. . . . . . . . 9 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → 𝑗 ∈ ℤ)
45		exprecap 10848	. . . . . . . . 9 ⊢ ((2 ∈ ℂ ∧ 2 # 0 ∧ 𝑗 ∈ ℤ) → ((1 / 2)↑𝑗) = (1 / (2↑𝑗)))
46	41, 42, 44, 45	mp3an12i 1377	. . . . . . . 8 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → ((1 / 2)↑𝑗) = (1 / (2↑𝑗)))
47	26, 46	eqtrd 2263	. . . . . . 7 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → ((𝑘 ∈ ℕ₀ ↦ ((1 / 2)↑𝑘))‘𝑗) = (1 / (2↑𝑗)))
48	47	oveq2d 6039	. . . . . 6 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → (𝐴 · ((𝑘 ∈ ℕ₀ ↦ ((1 / 2)↑𝑘))‘𝑗)) = (𝐴 · (1 / (2↑𝑗))))
49	34, 40, 48	3eqtr4d 2273	. . . . 5 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → (𝐹‘𝑗) = (𝐴 · ((𝑘 ∈ ℕ₀ ↦ ((1 / 2)↑𝑘))‘𝑗)))
50	1, 2, 12, 13, 18, 27, 49	climmulc2 11914	. . . 4 ⊢ (𝐴 ∈ ℂ → 𝐹 ⇝ (𝐴 · 0))
51		mul01 8573	. . . 4 ⊢ (𝐴 ∈ ℂ → (𝐴 · 0) = 0)
52	50, 51	breqtrd 4115	. . 3 ⊢ (𝐴 ∈ ℂ → 𝐹 ⇝ 0)
53		seqex 10717	. . . 4 ⊢ seq1( + , 𝐹) ∈ V
54	53	a1i 9	. . 3 ⊢ (𝐴 ∈ ℂ → seq1( + , 𝐹) ∈ V)
55	40, 36	eqeltrd 2307	. . 3 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → (𝐹‘𝑗) ∈ ℂ)
56	40	oveq2d 6039	. . . 4 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → (𝐴 − (𝐹‘𝑗)) = (𝐴 − (𝐴 / (2↑𝑗))))
57		geo2sum 12098	. . . . 5 ⊢ ((𝑗 ∈ ℕ ∧ 𝐴 ∈ ℂ) → Σ𝑛 ∈ (1...𝑗)(𝐴 / (2↑𝑛)) = (𝐴 − (𝐴 / (2↑𝑗))))
58	57	ancoms 268	. . . 4 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → Σ𝑛 ∈ (1...𝑗)(𝐴 / (2↑𝑛)) = (𝐴 − (𝐴 / (2↑𝑗))))
59		elnnuz 9798	. . . . . . . 8 ⊢ (𝑛 ∈ ℕ ↔ 𝑛 ∈ (ℤ_≥‘1))
60	59	biimpri 133	. . . . . . 7 ⊢ (𝑛 ∈ (ℤ_≥‘1) → 𝑛 ∈ ℕ)
61	60	adantl 277	. . . . . 6 ⊢ (((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) ∧ 𝑛 ∈ (ℤ_≥‘1)) → 𝑛 ∈ ℕ)
62		simpll 527	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) ∧ 𝑛 ∈ (ℤ_≥‘1)) → 𝐴 ∈ ℂ)
63	41	a1i 9	. . . . . . . 8 ⊢ (((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) ∧ 𝑛 ∈ (ℤ_≥‘1)) → 2 ∈ ℂ)
64	61	nnnn0d 9460	. . . . . . . 8 ⊢ (((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) ∧ 𝑛 ∈ (ℤ_≥‘1)) → 𝑛 ∈ ℕ₀)
65	63, 64	expcld 10941	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) ∧ 𝑛 ∈ (ℤ_≥‘1)) → (2↑𝑛) ∈ ℂ)
66	42	a1i 9	. . . . . . . 8 ⊢ (((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) ∧ 𝑛 ∈ (ℤ_≥‘1)) → 2 # 0)
67	61	nnzd 9606	. . . . . . . 8 ⊢ (((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) ∧ 𝑛 ∈ (ℤ_≥‘1)) → 𝑛 ∈ ℤ)
68	63, 66, 67	expap0d 10947	. . . . . . 7 ⊢ (((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) ∧ 𝑛 ∈ (ℤ_≥‘1)) → (2↑𝑛) # 0)
69	62, 65, 68	divclapd 8975	. . . . . 6 ⊢ (((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) ∧ 𝑛 ∈ (ℤ_≥‘1)) → (𝐴 / (2↑𝑛)) ∈ ℂ)
70		oveq2 6031	. . . . . . . 8 ⊢ (𝑘 = 𝑛 → (2↑𝑘) = (2↑𝑛))
71	70	oveq2d 6039	. . . . . . 7 ⊢ (𝑘 = 𝑛 → (𝐴 / (2↑𝑘)) = (𝐴 / (2↑𝑛)))
72	71, 14	fvmptg 5725	. . . . . 6 ⊢ ((𝑛 ∈ ℕ ∧ (𝐴 / (2↑𝑛)) ∈ ℂ) → (𝐹‘𝑛) = (𝐴 / (2↑𝑛)))
73	61, 69, 72	syl2anc 411	. . . . 5 ⊢ (((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) ∧ 𝑛 ∈ (ℤ_≥‘1)) → (𝐹‘𝑛) = (𝐴 / (2↑𝑛)))
74	35, 1	eleqtrdi 2323	. . . . 5 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → 𝑗 ∈ (ℤ_≥‘1))
75	73, 74, 69	fsum3ser 11981	. . . 4 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → Σ𝑛 ∈ (1...𝑗)(𝐴 / (2↑𝑛)) = (seq1( + , 𝐹)‘𝑗))
76	56, 58, 75	3eqtr2rd 2270	. . 3 ⊢ ((𝐴 ∈ ℂ ∧ 𝑗 ∈ ℕ) → (seq1( + , 𝐹)‘𝑗) = (𝐴 − (𝐹‘𝑗)))
77	1, 2, 52, 13, 54, 55, 76	climsubc2 11916	. 2 ⊢ (𝐴 ∈ ℂ → seq1( + , 𝐹) ⇝ (𝐴 − 0))
78		subid1 8404	. 2 ⊢ (𝐴 ∈ ℂ → (𝐴 − 0) = 𝐴)
79	77, 78	breqtrd 4115	1 ⊢ (𝐴 ∈ ℂ → seq1( + , 𝐹) ⇝ 𝐴)

Colors of variables: wff set class

Syntax hints: → wi 4 ∧ wa 104 = wceq 1397 ∈ wcel 2201 Vcvv 2801 class class class wbr 4089 ↦ cmpt 4151 ‘cfv 5328 (class class class)co 6023 ℂcc 8035 ℝcr 8036 0cc0 8037 1c1 8038 + caddc 8040 · cmul 8042 < clt 8219 ≤ cle 8220 − cmin 8355 # cap 8766 / cdiv 8857 ℕcn 9148 2c2 9199 ℕ₀cn0 9407 ℤcz 9484 ℤ_≥cuz 9760 ...cfz 10248 seqcseq 10715 ↑cexp 10806 abscabs 11580 ⇝ cli 11861 Σcsu 11936

This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 106 ax-ia2 107 ax-ia3 108 ax-in1 619 ax-in2 620 ax-io 716 ax-5 1495 ax-7 1496 ax-gen 1497 ax-ie1 1541 ax-ie2 1542 ax-8 1552 ax-10 1553 ax-11 1554 ax-i12 1555 ax-bndl 1557 ax-4 1558 ax-17 1574 ax-i9 1578 ax-ial 1582 ax-i5r 1583 ax-13 2203 ax-14 2204 ax-ext 2212 ax-coll 4205 ax-sep 4208 ax-nul 4216 ax-pow 4266 ax-pr 4301 ax-un 4532 ax-setind 4637 ax-iinf 4688 ax-cnex 8128 ax-resscn 8129 ax-1cn 8130 ax-1re 8131 ax-icn 8132 ax-addcl 8133 ax-addrcl 8134 ax-mulcl 8135 ax-mulrcl 8136 ax-addcom 8137 ax-mulcom 8138 ax-addass 8139 ax-mulass 8140 ax-distr 8141 ax-i2m1 8142 ax-0lt1 8143 ax-1rid 8144 ax-0id 8145 ax-rnegex 8146 ax-precex 8147 ax-cnre 8148 ax-pre-ltirr 8149 ax-pre-ltwlin 8150 ax-pre-lttrn 8151 ax-pre-apti 8152 ax-pre-ltadd 8153 ax-pre-mulgt0 8154 ax-pre-mulext 8155 ax-arch 8156 ax-caucvg 8157

This theorem depends on definitions: df-bi 117 df-dc 842 df-3or 1005 df-3an 1006 df-tru 1400 df-fal 1403 df-nf 1509 df-sb 1810 df-eu 2081 df-mo 2082 df-clab 2217 df-cleq 2223 df-clel 2226 df-nfc 2362 df-ne 2402 df-nel 2497 df-ral 2514 df-rex 2515 df-reu 2516 df-rmo 2517 df-rab 2518 df-v 2803 df-sbc 3031 df-csb 3127 df-dif 3201 df-un 3203 df-in 3205 df-ss 3212 df-nul 3494 df-if 3605 df-pw 3655 df-sn 3676 df-pr 3677 df-op 3679 df-uni 3895 df-int 3930 df-iun 3973 df-br 4090 df-opab 4152 df-mpt 4153 df-tr 4189 df-id 4392 df-po 4395 df-iso 4396 df-iord 4465 df-on 4467 df-ilim 4468 df-suc 4470 df-iom 4691 df-xp 4733 df-rel 4734 df-cnv 4735 df-co 4736 df-dm 4737 df-rn 4738 df-res 4739 df-ima 4740 df-iota 5288 df-fun 5330 df-fn 5331 df-f 5332 df-f1 5333 df-fo 5334 df-f1o 5335 df-fv 5336 df-isom 5337 df-riota 5976 df-ov 6026 df-oprab 6027 df-mpo 6028 df-1st 6308 df-2nd 6309 df-recs 6476 df-irdg 6541 df-frec 6562 df-1o 6587 df-oadd 6591 df-er 6707 df-en 6915 df-dom 6916 df-fin 6917 df-pnf 8221 df-mnf 8222 df-xr 8223 df-ltxr 8224 df-le 8225 df-sub 8357 df-neg 8358 df-reap 8760 df-ap 8767 df-div 8858 df-inn 9149 df-2 9207 df-3 9208 df-4 9209 df-n0 9408 df-z 9485 df-uz 9761 df-q 9859 df-rp 9894 df-fz 10249 df-fzo 10383 df-seqfrec 10716 df-exp 10807 df-ihash 11044 df-cj 11425 df-re 11426 df-im 11427 df-rsqrt 11581 df-abs 11582 df-clim 11862 df-sumdc 11937

This theorem is referenced by: trilpolemeq1 16711

W3C validator