Metamath Proof Explorer


Theorem clim1fr1

Description: A class of sequences of fractions that converge to 1. (Contributed by Glauco Siliprandi, 29-Jun-2017)

Ref Expression
Hypotheses clim1fr1.1 F = n A n + B A n
clim1fr1.2 φ A
clim1fr1.3 φ A 0
clim1fr1.4 φ B
Assertion clim1fr1 φ F 1

Proof

Step Hyp Ref Expression
1 clim1fr1.1 F = n A n + B A n
2 clim1fr1.2 φ A
3 clim1fr1.3 φ A 0
4 clim1fr1.4 φ B
5 nnuz = 1
6 1zzd φ 1
7 nnex V
8 7 mptex n 1 V
9 8 a1i φ n 1 V
10 1cnd φ 1
11 eqidd k n 1 = n 1
12 eqidd k n = k 1 = 1
13 id k k
14 1cnd k 1
15 11 12 13 14 fvmptd k n 1 k = 1
16 15 adantl φ k n 1 k = 1
17 5 6 9 10 16 climconst φ n 1 1
18 7 mptex n A n + B A n V
19 1 18 eqeltri F V
20 19 a1i φ F V
21 4 adantr φ n B
22 2 adantr φ n A
23 nncn n n
24 23 adantl φ n n
25 3 adantr φ n A 0
26 nnne0 n n 0
27 26 adantl φ n n 0
28 21 22 24 25 27 divdiv1d φ n B A n = B A n
29 28 mpteq2dva φ n B A n = n B A n
30 4 2 3 divcld φ B A
31 divcnv B A n B A n 0
32 30 31 syl φ n B A n 0
33 29 32 eqbrtrrd φ n B A n 0
34 eqid n 1 = n 1
35 1cnd n 1
36 34 35 fmpti n 1 :
37 36 a1i φ n 1 :
38 37 ffvelrnda φ k n 1 k
39 22 24 mulcld φ n A n
40 22 24 25 27 mulne0d φ n A n 0
41 21 39 40 divcld φ n B A n
42 41 fmpttd φ n B A n :
43 42 ffvelrnda φ k n B A n k
44 oveq2 n = k A n = A k
45 44 oveq1d n = k A n + B = A k + B
46 45 44 oveq12d n = k A n + B A n = A k + B A k
47 simpr φ k k
48 2 adantr φ k A
49 47 nncnd φ k k
50 48 49 mulcld φ k A k
51 4 adantr φ k B
52 50 51 addcld φ k A k + B
53 3 adantr φ k A 0
54 47 nnne0d φ k k 0
55 48 49 53 54 mulne0d φ k A k 0
56 52 50 55 divcld φ k A k + B A k
57 1 46 47 56 fvmptd3 φ k F k = A k + B A k
58 50 51 50 55 divdird φ k A k + B A k = A k A k + B A k
59 50 55 dividd φ k A k A k = 1
60 59 oveq1d φ k A k A k + B A k = 1 + B A k
61 58 60 eqtrd φ k A k + B A k = 1 + B A k
62 16 eqcomd φ k 1 = n 1 k
63 eqidd φ k n B A n = n B A n
64 simpr φ k n = k n = k
65 64 oveq2d φ k n = k A n = A k
66 65 oveq2d φ k n = k B A n = B A k
67 51 50 55 divcld φ k B A k
68 63 66 47 67 fvmptd φ k n B A n k = B A k
69 68 eqcomd φ k B A k = n B A n k
70 62 69 oveq12d φ k 1 + B A k = n 1 k + n B A n k
71 57 61 70 3eqtrd φ k F k = n 1 k + n B A n k
72 5 6 17 20 33 38 43 71 climadd φ F 1 + 0
73 1p0e1 1 + 0 = 1
74 72 73 breqtrdi φ F 1