atantayl2 - Metamath Proof Explorer

	Metamath Proof Explorer		< Previous Next > Nearby theorems
Mirrors > Home > MPE Home > Th. List > atantayl2		Structured version Visualization version GIF version

Theorem atantayl2 26325

Description: The Taylor series for arctan(𝐴). (Contributed by Mario Carneiro, 1-Apr-2015.)

**Hypothesis**
Ref	Expression
atantayl2.1	⊢ 𝐹 = (𝑛 ∈ ℕ ↦ if(2 ∥ 𝑛, 0, ((-1↑((𝑛 − 1) / 2)) · ((𝐴↑𝑛) / 𝑛))))

**Assertion**
Ref	Expression
atantayl2	⊢ ((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) → seq1( + , 𝐹) ⇝ (arctan‘𝐴))

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

**Proof of Theorem atantayl2**
Step	Hyp	Ref	Expression
1		atantayl2.1	. . . 4 ⊢ 𝐹 = (𝑛 ∈ ℕ ↦ if(2 ∥ 𝑛, 0, ((-1↑((𝑛 − 1) / 2)) · ((𝐴↑𝑛) / 𝑛))))
2		ax-icn 11119	. . . . . . . . . . . . . . . 16 ⊢ i ∈ ℂ
3	2	negcli 11478	. . . . . . . . . . . . . . 15 ⊢ -i ∈ ℂ
4	3	a1i 11	. . . . . . . . . . . . . 14 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → -i ∈ ℂ)
5		nnnn0 12429	. . . . . . . . . . . . . . 15 ⊢ (𝑛 ∈ ℕ → 𝑛 ∈ ℕ₀)
6	5	ad2antlr 725	. . . . . . . . . . . . . 14 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → 𝑛 ∈ ℕ₀)
7	4, 6	expcld 14061	. . . . . . . . . . . . 13 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → (-i↑𝑛) ∈ ℂ)
8		sqneg 14031	. . . . . . . . . . . . . . . . 17 ⊢ (i ∈ ℂ → (-i↑2) = (i↑2))
9	2, 8	ax-mp 5	. . . . . . . . . . . . . . . 16 ⊢ (-i↑2) = (i↑2)
10	9	oveq1i 7372	. . . . . . . . . . . . . . 15 ⊢ ((-i↑2)↑(𝑛 / 2)) = ((i↑2)↑(𝑛 / 2))
11		ine0 11599	. . . . . . . . . . . . . . . . . 18 ⊢ i ≠ 0
12	2, 11	negne0i 11485	. . . . . . . . . . . . . . . . 17 ⊢ -i ≠ 0
13	12	a1i 11	. . . . . . . . . . . . . . . 16 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → -i ≠ 0)
14		2z 12544	. . . . . . . . . . . . . . . . 17 ⊢ 2 ∈ ℤ
15	14	a1i 11	. . . . . . . . . . . . . . . 16 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → 2 ∈ ℤ)
16		2ne0 12266	. . . . . . . . . . . . . . . . . 18 ⊢ 2 ≠ 0
17		nnz 12529	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑛 ∈ ℕ → 𝑛 ∈ ℤ)
18	17	adantl 482	. . . . . . . . . . . . . . . . . 18 ⊢ (((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) → 𝑛 ∈ ℤ)
19		dvdsval2 16150	. . . . . . . . . . . . . . . . . 18 ⊢ ((2 ∈ ℤ ∧ 2 ≠ 0 ∧ 𝑛 ∈ ℤ) → (2 ∥ 𝑛 ↔ (𝑛 / 2) ∈ ℤ))
20	14, 16, 18, 19	mp3an12i 1465	. . . . . . . . . . . . . . . . 17 ⊢ (((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) → (2 ∥ 𝑛 ↔ (𝑛 / 2) ∈ ℤ))
21	20	biimpa 477	. . . . . . . . . . . . . . . 16 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → (𝑛 / 2) ∈ ℤ)
22		expmulz 14024	. . . . . . . . . . . . . . . 16 ⊢ (((-i ∈ ℂ ∧ -i ≠ 0) ∧ (2 ∈ ℤ ∧ (𝑛 / 2) ∈ ℤ)) → (-i↑(2 · (𝑛 / 2))) = ((-i↑2)↑(𝑛 / 2)))
23	4, 13, 15, 21, 22	syl22anc 837	. . . . . . . . . . . . . . 15 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → (-i↑(2 · (𝑛 / 2))) = ((-i↑2)↑(𝑛 / 2)))
24	2	a1i 11	. . . . . . . . . . . . . . . 16 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → i ∈ ℂ)
25	11	a1i 11	. . . . . . . . . . . . . . . 16 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → i ≠ 0)
26		expmulz 14024	. . . . . . . . . . . . . . . 16 ⊢ (((i ∈ ℂ ∧ i ≠ 0) ∧ (2 ∈ ℤ ∧ (𝑛 / 2) ∈ ℤ)) → (i↑(2 · (𝑛 / 2))) = ((i↑2)↑(𝑛 / 2)))
27	24, 25, 15, 21, 26	syl22anc 837	. . . . . . . . . . . . . . 15 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → (i↑(2 · (𝑛 / 2))) = ((i↑2)↑(𝑛 / 2)))
28	10, 23, 27	3eqtr4a 2797	. . . . . . . . . . . . . 14 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → (-i↑(2 · (𝑛 / 2))) = (i↑(2 · (𝑛 / 2))))
29		nncn 12170	. . . . . . . . . . . . . . . . 17 ⊢ (𝑛 ∈ ℕ → 𝑛 ∈ ℂ)
30	29	ad2antlr 725	. . . . . . . . . . . . . . . 16 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → 𝑛 ∈ ℂ)
31		2cnd 12240	. . . . . . . . . . . . . . . 16 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → 2 ∈ ℂ)
32	16	a1i 11	. . . . . . . . . . . . . . . 16 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → 2 ≠ 0)
33	30, 31, 32	divcan2d 11942	. . . . . . . . . . . . . . 15 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → (2 · (𝑛 / 2)) = 𝑛)
34	33	oveq2d 7378	. . . . . . . . . . . . . 14 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → (-i↑(2 · (𝑛 / 2))) = (-i↑𝑛))
35	33	oveq2d 7378	. . . . . . . . . . . . . 14 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → (i↑(2 · (𝑛 / 2))) = (i↑𝑛))
36	28, 34, 35	3eqtr3d 2779	. . . . . . . . . . . . 13 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → (-i↑𝑛) = (i↑𝑛))
37	7, 36	subeq0bd 11590	. . . . . . . . . . . 12 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → ((-i↑𝑛) − (i↑𝑛)) = 0)
38	37	oveq2d 7378	. . . . . . . . . . 11 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → (i · ((-i↑𝑛) − (i↑𝑛))) = (i · 0))
39		it0e0 12384	. . . . . . . . . . 11 ⊢ (i · 0) = 0
40	38, 39	eqtrdi 2787	. . . . . . . . . 10 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → (i · ((-i↑𝑛) − (i↑𝑛))) = 0)
41	40	oveq1d 7377	. . . . . . . . 9 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → ((i · ((-i↑𝑛) − (i↑𝑛))) / 2) = (0 / 2))
42		2cn 12237	. . . . . . . . . 10 ⊢ 2 ∈ ℂ
43	42, 16	div0i 11898	. . . . . . . . 9 ⊢ (0 / 2) = 0
44	41, 43	eqtrdi 2787	. . . . . . . 8 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → ((i · ((-i↑𝑛) − (i↑𝑛))) / 2) = 0)
45	44	oveq1d 7377	. . . . . . 7 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → (((i · ((-i↑𝑛) − (i↑𝑛))) / 2) · ((𝐴↑𝑛) / 𝑛)) = (0 · ((𝐴↑𝑛) / 𝑛)))
46		simplll 773	. . . . . . . . . 10 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → 𝐴 ∈ ℂ)
47	46, 6	expcld 14061	. . . . . . . . 9 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → (𝐴↑𝑛) ∈ ℂ)
48		nnne0 12196	. . . . . . . . . 10 ⊢ (𝑛 ∈ ℕ → 𝑛 ≠ 0)
49	48	ad2antlr 725	. . . . . . . . 9 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → 𝑛 ≠ 0)
50	47, 30, 49	divcld 11940	. . . . . . . 8 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → ((𝐴↑𝑛) / 𝑛) ∈ ℂ)
51	50	mul02d 11362	. . . . . . 7 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → (0 · ((𝐴↑𝑛) / 𝑛)) = 0)
52	45, 51	eqtr2d 2772	. . . . . 6 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ 2 ∥ 𝑛) → 0 = (((i · ((-i↑𝑛) − (i↑𝑛))) / 2) · ((𝐴↑𝑛) / 𝑛)))
53		2cnd 12240	. . . . . . . 8 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → 2 ∈ ℂ)
54		ax-1cn 11118	. . . . . . . . . . 11 ⊢ 1 ∈ ℂ
55	54	negcli 11478	. . . . . . . . . 10 ⊢ -1 ∈ ℂ
56	55	a1i 11	. . . . . . . . 9 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → -1 ∈ ℂ)
57		neg1ne0 12278	. . . . . . . . . 10 ⊢ -1 ≠ 0
58	57	a1i 11	. . . . . . . . 9 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → -1 ≠ 0)
59	29	ad2antlr 725	. . . . . . . . . . . . . 14 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → 𝑛 ∈ ℂ)
60		peano2cn 11336	. . . . . . . . . . . . . 14 ⊢ (𝑛 ∈ ℂ → (𝑛 + 1) ∈ ℂ)
61	59, 60	syl 17	. . . . . . . . . . . . 13 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (𝑛 + 1) ∈ ℂ)
62	16	a1i 11	. . . . . . . . . . . . 13 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → 2 ≠ 0)
63	61, 53, 53, 62	divsubdird 11979	. . . . . . . . . . . 12 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (((𝑛 + 1) − 2) / 2) = (((𝑛 + 1) / 2) − (2 / 2)))
64		2div2e1 12303	. . . . . . . . . . . . 13 ⊢ (2 / 2) = 1
65	64	oveq2i 7373	. . . . . . . . . . . 12 ⊢ (((𝑛 + 1) / 2) − (2 / 2)) = (((𝑛 + 1) / 2) − 1)
66	63, 65	eqtrdi 2787	. . . . . . . . . . 11 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (((𝑛 + 1) − 2) / 2) = (((𝑛 + 1) / 2) − 1))
67		df-2 12225	. . . . . . . . . . . . . 14 ⊢ 2 = (1 + 1)
68	67	oveq2i 7373	. . . . . . . . . . . . 13 ⊢ ((𝑛 + 1) − 2) = ((𝑛 + 1) − (1 + 1))
69	54	a1i 11	. . . . . . . . . . . . . 14 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → 1 ∈ ℂ)
70	59, 69, 69	pnpcan2d 11559	. . . . . . . . . . . . 13 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → ((𝑛 + 1) − (1 + 1)) = (𝑛 − 1))
71	68, 70	eqtrid 2783	. . . . . . . . . . . 12 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → ((𝑛 + 1) − 2) = (𝑛 − 1))
72	71	oveq1d 7377	. . . . . . . . . . 11 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (((𝑛 + 1) − 2) / 2) = ((𝑛 − 1) / 2))
73	66, 72	eqtr3d 2773	. . . . . . . . . 10 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (((𝑛 + 1) / 2) − 1) = ((𝑛 − 1) / 2))
74	20	notbid 317	. . . . . . . . . . . . 13 ⊢ (((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) → (¬ 2 ∥ 𝑛 ↔ ¬ (𝑛 / 2) ∈ ℤ))
75		zeo 12598	. . . . . . . . . . . . . . 15 ⊢ (𝑛 ∈ ℤ → ((𝑛 / 2) ∈ ℤ ∨ ((𝑛 + 1) / 2) ∈ ℤ))
76	18, 75	syl 17	. . . . . . . . . . . . . 14 ⊢ (((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) → ((𝑛 / 2) ∈ ℤ ∨ ((𝑛 + 1) / 2) ∈ ℤ))
77	76	ord 862	. . . . . . . . . . . . 13 ⊢ (((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) → (¬ (𝑛 / 2) ∈ ℤ → ((𝑛 + 1) / 2) ∈ ℤ))
78	74, 77	sylbid 239	. . . . . . . . . . . 12 ⊢ (((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) → (¬ 2 ∥ 𝑛 → ((𝑛 + 1) / 2) ∈ ℤ))
79	78	imp 407	. . . . . . . . . . 11 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → ((𝑛 + 1) / 2) ∈ ℤ)
80		peano2zm 12555	. . . . . . . . . . 11 ⊢ (((𝑛 + 1) / 2) ∈ ℤ → (((𝑛 + 1) / 2) − 1) ∈ ℤ)
81	79, 80	syl 17	. . . . . . . . . 10 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (((𝑛 + 1) / 2) − 1) ∈ ℤ)
82	73, 81	eqeltrrd 2833	. . . . . . . . 9 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → ((𝑛 − 1) / 2) ∈ ℤ)
83	56, 58, 82	expclzd 14066	. . . . . . . 8 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (-1↑((𝑛 − 1) / 2)) ∈ ℂ)
84	83	2timesd 12405	. . . . . . . . 9 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (2 · (-1↑((𝑛 − 1) / 2))) = ((-1↑((𝑛 − 1) / 2)) + (-1↑((𝑛 − 1) / 2))))
85		subcl 11409	. . . . . . . . . . . . . . . 16 ⊢ ((𝑛 ∈ ℂ ∧ 1 ∈ ℂ) → (𝑛 − 1) ∈ ℂ)
86	59, 54, 85	sylancl 586	. . . . . . . . . . . . . . 15 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (𝑛 − 1) ∈ ℂ)
87	86, 53, 62	divcan2d 11942	. . . . . . . . . . . . . 14 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (2 · ((𝑛 − 1) / 2)) = (𝑛 − 1))
88	87	oveq2d 7378	. . . . . . . . . . . . 13 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (-i↑(2 · ((𝑛 − 1) / 2))) = (-i↑(𝑛 − 1)))
89	3	a1i 11	. . . . . . . . . . . . . 14 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → -i ∈ ℂ)
90	12	a1i 11	. . . . . . . . . . . . . 14 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → -i ≠ 0)
91	17	ad2antlr 725	. . . . . . . . . . . . . 14 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → 𝑛 ∈ ℤ)
92	89, 90, 91	expm1d 14071	. . . . . . . . . . . . 13 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (-i↑(𝑛 − 1)) = ((-i↑𝑛) / -i))
93	88, 92	eqtrd 2771	. . . . . . . . . . . 12 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (-i↑(2 · ((𝑛 − 1) / 2))) = ((-i↑𝑛) / -i))
94	14	a1i 11	. . . . . . . . . . . . 13 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → 2 ∈ ℤ)
95		expmulz 14024	. . . . . . . . . . . . 13 ⊢ (((-i ∈ ℂ ∧ -i ≠ 0) ∧ (2 ∈ ℤ ∧ ((𝑛 − 1) / 2) ∈ ℤ)) → (-i↑(2 · ((𝑛 − 1) / 2))) = ((-i↑2)↑((𝑛 − 1) / 2)))
96	89, 90, 94, 82, 95	syl22anc 837	. . . . . . . . . . . 12 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (-i↑(2 · ((𝑛 − 1) / 2))) = ((-i↑2)↑((𝑛 − 1) / 2)))
97	5	ad2antlr 725	. . . . . . . . . . . . . 14 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → 𝑛 ∈ ℕ₀)
98		expcl 13995	. . . . . . . . . . . . . 14 ⊢ ((-i ∈ ℂ ∧ 𝑛 ∈ ℕ₀) → (-i↑𝑛) ∈ ℂ)
99	3, 97, 98	sylancr 587	. . . . . . . . . . . . 13 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (-i↑𝑛) ∈ ℂ)
100	99, 89, 90	divrec2d 11944	. . . . . . . . . . . 12 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → ((-i↑𝑛) / -i) = ((1 / -i) · (-i↑𝑛)))
101	93, 96, 100	3eqtr3d 2779	. . . . . . . . . . 11 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → ((-i↑2)↑((𝑛 − 1) / 2)) = ((1 / -i) · (-i↑𝑛)))
102		i2 14116	. . . . . . . . . . . . 13 ⊢ (i↑2) = -1
103	9, 102	eqtri 2759	. . . . . . . . . . . 12 ⊢ (-i↑2) = -1
104	103	oveq1i 7372	. . . . . . . . . . 11 ⊢ ((-i↑2)↑((𝑛 − 1) / 2)) = (-1↑((𝑛 − 1) / 2))
105		irec 14115	. . . . . . . . . . . . . 14 ⊢ (1 / i) = -i
106	105	negeqi 11403	. . . . . . . . . . . . 13 ⊢ -(1 / i) = --i
107		divneg2 11888	. . . . . . . . . . . . . 14 ⊢ ((1 ∈ ℂ ∧ i ∈ ℂ ∧ i ≠ 0) → -(1 / i) = (1 / -i))
108	54, 2, 11, 107	mp3an 1461	. . . . . . . . . . . . 13 ⊢ -(1 / i) = (1 / -i)
109	2	negnegi 11480	. . . . . . . . . . . . 13 ⊢ --i = i
110	106, 108, 109	3eqtr3i 2767	. . . . . . . . . . . 12 ⊢ (1 / -i) = i
111	110	oveq1i 7372	. . . . . . . . . . 11 ⊢ ((1 / -i) · (-i↑𝑛)) = (i · (-i↑𝑛))
112	101, 104, 111	3eqtr3g 2794	. . . . . . . . . 10 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (-1↑((𝑛 − 1) / 2)) = (i · (-i↑𝑛)))
113	87	oveq2d 7378	. . . . . . . . . . . . . 14 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (i↑(2 · ((𝑛 − 1) / 2))) = (i↑(𝑛 − 1)))
114	2	a1i 11	. . . . . . . . . . . . . . 15 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → i ∈ ℂ)
115	11	a1i 11	. . . . . . . . . . . . . . 15 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → i ≠ 0)
116	114, 115, 91	expm1d 14071	. . . . . . . . . . . . . 14 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (i↑(𝑛 − 1)) = ((i↑𝑛) / i))
117	113, 116	eqtrd 2771	. . . . . . . . . . . . 13 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (i↑(2 · ((𝑛 − 1) / 2))) = ((i↑𝑛) / i))
118		expmulz 14024	. . . . . . . . . . . . . 14 ⊢ (((i ∈ ℂ ∧ i ≠ 0) ∧ (2 ∈ ℤ ∧ ((𝑛 − 1) / 2) ∈ ℤ)) → (i↑(2 · ((𝑛 − 1) / 2))) = ((i↑2)↑((𝑛 − 1) / 2)))
119	114, 115, 94, 82, 118	syl22anc 837	. . . . . . . . . . . . 13 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (i↑(2 · ((𝑛 − 1) / 2))) = ((i↑2)↑((𝑛 − 1) / 2)))
120		expcl 13995	. . . . . . . . . . . . . . 15 ⊢ ((i ∈ ℂ ∧ 𝑛 ∈ ℕ₀) → (i↑𝑛) ∈ ℂ)
121	2, 97, 120	sylancr 587	. . . . . . . . . . . . . 14 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (i↑𝑛) ∈ ℂ)
122	121, 114, 115	divrec2d 11944	. . . . . . . . . . . . 13 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → ((i↑𝑛) / i) = ((1 / i) · (i↑𝑛)))
123	117, 119, 122	3eqtr3d 2779	. . . . . . . . . . . 12 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → ((i↑2)↑((𝑛 − 1) / 2)) = ((1 / i) · (i↑𝑛)))
124	102	oveq1i 7372	. . . . . . . . . . . 12 ⊢ ((i↑2)↑((𝑛 − 1) / 2)) = (-1↑((𝑛 − 1) / 2))
125	105	oveq1i 7372	. . . . . . . . . . . 12 ⊢ ((1 / i) · (i↑𝑛)) = (-i · (i↑𝑛))
126	123, 124, 125	3eqtr3g 2794	. . . . . . . . . . 11 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (-1↑((𝑛 − 1) / 2)) = (-i · (i↑𝑛)))
127		mulneg1 11600	. . . . . . . . . . . 12 ⊢ ((i ∈ ℂ ∧ (i↑𝑛) ∈ ℂ) → (-i · (i↑𝑛)) = -(i · (i↑𝑛)))
128	2, 121, 127	sylancr 587	. . . . . . . . . . 11 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (-i · (i↑𝑛)) = -(i · (i↑𝑛)))
129	126, 128	eqtrd 2771	. . . . . . . . . 10 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (-1↑((𝑛 − 1) / 2)) = -(i · (i↑𝑛)))
130	112, 129	oveq12d 7380	. . . . . . . . 9 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → ((-1↑((𝑛 − 1) / 2)) + (-1↑((𝑛 − 1) / 2))) = ((i · (-i↑𝑛)) + -(i · (i↑𝑛))))
131		mulcl 11144	. . . . . . . . . . . 12 ⊢ ((i ∈ ℂ ∧ (-i↑𝑛) ∈ ℂ) → (i · (-i↑𝑛)) ∈ ℂ)
132	2, 99, 131	sylancr 587	. . . . . . . . . . 11 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (i · (-i↑𝑛)) ∈ ℂ)
133		mulcl 11144	. . . . . . . . . . . 12 ⊢ ((i ∈ ℂ ∧ (i↑𝑛) ∈ ℂ) → (i · (i↑𝑛)) ∈ ℂ)
134	2, 121, 133	sylancr 587	. . . . . . . . . . 11 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (i · (i↑𝑛)) ∈ ℂ)
135	132, 134	negsubd 11527	. . . . . . . . . 10 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → ((i · (-i↑𝑛)) + -(i · (i↑𝑛))) = ((i · (-i↑𝑛)) − (i · (i↑𝑛))))
136	114, 99, 121	subdid 11620	. . . . . . . . . 10 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (i · ((-i↑𝑛) − (i↑𝑛))) = ((i · (-i↑𝑛)) − (i · (i↑𝑛))))
137	135, 136	eqtr4d 2774	. . . . . . . . 9 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → ((i · (-i↑𝑛)) + -(i · (i↑𝑛))) = (i · ((-i↑𝑛) − (i↑𝑛))))
138	84, 130, 137	3eqtrd 2775	. . . . . . . 8 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (2 · (-1↑((𝑛 − 1) / 2))) = (i · ((-i↑𝑛) − (i↑𝑛))))
139	53, 83, 62, 138	mvllmuld 11996	. . . . . . 7 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → (-1↑((𝑛 − 1) / 2)) = ((i · ((-i↑𝑛) − (i↑𝑛))) / 2))
140	139	oveq1d 7377	. . . . . 6 ⊢ ((((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) ∧ ¬ 2 ∥ 𝑛) → ((-1↑((𝑛 − 1) / 2)) · ((𝐴↑𝑛) / 𝑛)) = (((i · ((-i↑𝑛) − (i↑𝑛))) / 2) · ((𝐴↑𝑛) / 𝑛)))
141	52, 140	ifeqda 4527	. . . . 5 ⊢ (((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) ∧ 𝑛 ∈ ℕ) → if(2 ∥ 𝑛, 0, ((-1↑((𝑛 − 1) / 2)) · ((𝐴↑𝑛) / 𝑛))) = (((i · ((-i↑𝑛) − (i↑𝑛))) / 2) · ((𝐴↑𝑛) / 𝑛)))
142	141	mpteq2dva 5210	. . . 4 ⊢ ((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) → (𝑛 ∈ ℕ ↦ if(2 ∥ 𝑛, 0, ((-1↑((𝑛 − 1) / 2)) · ((𝐴↑𝑛) / 𝑛)))) = (𝑛 ∈ ℕ ↦ (((i · ((-i↑𝑛) − (i↑𝑛))) / 2) · ((𝐴↑𝑛) / 𝑛))))
143	1, 142	eqtrid 2783	. . 3 ⊢ ((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) → 𝐹 = (𝑛 ∈ ℕ ↦ (((i · ((-i↑𝑛) − (i↑𝑛))) / 2) · ((𝐴↑𝑛) / 𝑛))))
144	143	seqeq3d 13924	. 2 ⊢ ((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) → seq1( + , 𝐹) = seq1( + , (𝑛 ∈ ℕ ↦ (((i · ((-i↑𝑛) − (i↑𝑛))) / 2) · ((𝐴↑𝑛) / 𝑛)))))
145		eqid 2731	. . 3 ⊢ (𝑛 ∈ ℕ ↦ (((i · ((-i↑𝑛) − (i↑𝑛))) / 2) · ((𝐴↑𝑛) / 𝑛))) = (𝑛 ∈ ℕ ↦ (((i · ((-i↑𝑛) − (i↑𝑛))) / 2) · ((𝐴↑𝑛) / 𝑛)))
146	145	atantayl 26324	. 2 ⊢ ((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) → seq1( + , (𝑛 ∈ ℕ ↦ (((i · ((-i↑𝑛) − (i↑𝑛))) / 2) · ((𝐴↑𝑛) / 𝑛)))) ⇝ (arctan‘𝐴))
147	144, 146	eqbrtrd 5132	1 ⊢ ((𝐴 ∈ ℂ ∧ (abs‘𝐴) < 1) → seq1( + , 𝐹) ⇝ (arctan‘𝐴))

Colors of variables: wff setvar class

Syntax hints: ¬ wn 3 → wi 4 ↔ wb 205 ∧ wa 396 ∨ wo 845 = wceq 1541 ∈ wcel 2106 ≠ wne 2939 ifcif 4491 class class class wbr 5110 ↦ cmpt 5193 ‘cfv 6501 (class class class)co 7362 ℂcc 11058 0cc0 11060 1c1 11061 ici 11062 + caddc 11063 · cmul 11065 < clt 11198 − cmin 11394 -cneg 11395 / cdiv 11821 ℕcn 12162 2c2 12217 ℕ₀cn0 12422 ℤcz 12508 seqcseq 13916 ↑cexp 13977 abscabs 15131 ⇝ cli 15378 ∥ cdvds 16147 arctancatan 26251

This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1797 ax-4 1811 ax-5 1913 ax-6 1971 ax-7 2011 ax-8 2108 ax-9 2116 ax-10 2137 ax-11 2154 ax-12 2171 ax-ext 2702 ax-rep 5247 ax-sep 5261 ax-nul 5268 ax-pow 5325 ax-pr 5389 ax-un 7677 ax-inf2 9586 ax-cnex 11116 ax-resscn 11117 ax-1cn 11118 ax-icn 11119 ax-addcl 11120 ax-addrcl 11121 ax-mulcl 11122 ax-mulrcl 11123 ax-mulcom 11124 ax-addass 11125 ax-mulass 11126 ax-distr 11127 ax-i2m1 11128 ax-1ne0 11129 ax-1rid 11130 ax-rnegex 11131 ax-rrecex 11132 ax-cnre 11133 ax-pre-lttri 11134 ax-pre-lttrn 11135 ax-pre-ltadd 11136 ax-pre-mulgt0 11137 ax-pre-sup 11138 ax-addf 11139 ax-mulf 11140

This theorem depends on definitions: df-bi 206 df-an 397 df-or 846 df-3or 1088 df-3an 1089 df-tru 1544 df-fal 1554 df-ex 1782 df-nf 1786 df-sb 2068 df-mo 2533 df-eu 2562 df-clab 2709 df-cleq 2723 df-clel 2809 df-nfc 2884 df-ne 2940 df-nel 3046 df-ral 3061 df-rex 3070 df-rmo 3351 df-reu 3352 df-rab 3406 df-v 3448 df-sbc 3743 df-csb 3859 df-dif 3916 df-un 3918 df-in 3920 df-ss 3930 df-pss 3932 df-nul 4288 df-if 4492 df-pw 4567 df-sn 4592 df-pr 4594 df-tp 4596 df-op 4598 df-uni 4871 df-int 4913 df-iun 4961 df-iin 4962 df-br 5111 df-opab 5173 df-mpt 5194 df-tr 5228 df-id 5536 df-eprel 5542 df-po 5550 df-so 5551 df-fr 5593 df-se 5594 df-we 5595 df-xp 5644 df-rel 5645 df-cnv 5646 df-co 5647 df-dm 5648 df-rn 5649 df-res 5650 df-ima 5651 df-pred 6258 df-ord 6325 df-on 6326 df-lim 6327 df-suc 6328 df-iota 6453 df-fun 6503 df-fn 6504 df-f 6505 df-f1 6506 df-fo 6507 df-f1o 6508 df-fv 6509 df-isom 6510 df-riota 7318 df-ov 7365 df-oprab 7366 df-mpo 7367 df-of 7622 df-om 7808 df-1st 7926 df-2nd 7927 df-supp 8098 df-frecs 8217 df-wrecs 8248 df-recs 8322 df-rdg 8361 df-1o 8417 df-2o 8418 df-er 8655 df-map 8774 df-pm 8775 df-ixp 8843 df-en 8891 df-dom 8892 df-sdom 8893 df-fin 8894 df-fsupp 9313 df-fi 9356 df-sup 9387 df-inf 9388 df-oi 9455 df-card 9884 df-pnf 11200 df-mnf 11201 df-xr 11202 df-ltxr 11203 df-le 11204 df-sub 11396 df-neg 11397 df-div 11822 df-nn 12163 df-2 12225 df-3 12226 df-4 12227 df-5 12228 df-6 12229 df-7 12230 df-8 12231 df-9 12232 df-n0 12423 df-z 12509 df-dec 12628 df-uz 12773 df-q 12883 df-rp 12925 df-xneg 13042 df-xadd 13043 df-xmul 13044 df-ioo 13278 df-ioc 13279 df-ico 13280 df-icc 13281 df-fz 13435 df-fzo 13578 df-fl 13707 df-mod 13785 df-seq 13917 df-exp 13978 df-fac 14184 df-bc 14213 df-hash 14241 df-shft 14964 df-cj 14996 df-re 14997 df-im 14998 df-sqrt 15132 df-abs 15133 df-limsup 15365 df-clim 15382 df-rlim 15383 df-sum 15583 df-ef 15961 df-sin 15963 df-cos 15964 df-tan 15965 df-pi 15966 df-dvds 16148 df-struct 17030 df-sets 17047 df-slot 17065 df-ndx 17077 df-base 17095 df-ress 17124 df-plusg 17160 df-mulr 17161 df-starv 17162 df-sca 17163 df-vsca 17164 df-ip 17165 df-tset 17166 df-ple 17167 df-ds 17169 df-unif 17170 df-hom 17171 df-cco 17172 df-rest 17318 df-topn 17319 df-0g 17337 df-gsum 17338 df-topgen 17339 df-pt 17340 df-prds 17343 df-xrs 17398 df-qtop 17403 df-imas 17404 df-xps 17406 df-mre 17480 df-mrc 17481 df-acs 17483 df-mgm 18511 df-sgrp 18560 df-mnd 18571 df-submnd 18616 df-mulg 18887 df-cntz 19111 df-cmn 19578 df-psmet 20825 df-xmet 20826 df-met 20827 df-bl 20828 df-mopn 20829 df-fbas 20830 df-fg 20831 df-cnfld 20834 df-top 22280 df-topon 22297 df-topsp 22319 df-bases 22333 df-cld 22407 df-ntr 22408 df-cls 22409 df-nei 22486 df-lp 22524 df-perf 22525 df-cn 22615 df-cnp 22616 df-haus 22703 df-cmp 22775 df-tx 22950 df-hmeo 23143 df-fil 23234 df-fm 23326 df-flim 23327 df-flf 23328 df-xms 23710 df-ms 23711 df-tms 23712 df-cncf 24278 df-limc 25267 df-dv 25268 df-ulm 25773 df-log 25949 df-atan 26254

This theorem is referenced by: atantayl3 26326 leibpi 26329

W3C validator