Metamath Proof Explorer


Theorem fourierdlem4

Description: E is a function that maps any point to a periodic corresponding point in ( A , B ] . (Contributed by Glauco Siliprandi, 11-Dec-2019)

Ref Expression
Hypotheses fourierdlem4.a φ A
fourierdlem4.b φ B
fourierdlem4.altb φ A < B
fourierdlem4.t T = B A
fourierdlem4.e E = x x + B x T T
Assertion fourierdlem4 φ E : A B

Proof

Step Hyp Ref Expression
1 fourierdlem4.a φ A
2 fourierdlem4.b φ B
3 fourierdlem4.altb φ A < B
4 fourierdlem4.t T = B A
5 fourierdlem4.e E = x x + B x T T
6 simpr φ x x
7 2 adantr φ x B
8 7 6 resubcld φ x B x
9 2 1 resubcld φ B A
10 4 9 eqeltrid φ T
11 10 adantr φ x T
12 4 a1i φ T = B A
13 2 recnd φ B
14 1 recnd φ A
15 1 3 gtned φ B A
16 13 14 15 subne0d φ B A 0
17 12 16 eqnetrd φ T 0
18 17 adantr φ x T 0
19 8 11 18 redivcld φ x B x T
20 19 flcld φ x B x T
21 20 zred φ x B x T
22 21 11 remulcld φ x B x T T
23 6 22 readdcld φ x x + B x T T
24 1 adantr φ x A
25 24 6 resubcld φ x A x
26 25 11 18 redivcld φ x A x T
27 26 11 remulcld φ x A x T T
28 13 addid1d φ B + 0 = B
29 28 eqcomd φ B = B + 0
30 13 14 subcld φ B A
31 30 subidd φ B - A - B A = 0
32 31 eqcomd φ 0 = B - A - B A
33 32 oveq2d φ B + 0 = B + B A - B A
34 13 30 30 addsub12d φ B + B A - B A = B A + B - B A
35 13 14 nncand φ B B A = A
36 35 oveq2d φ B A + B - B A = B - A + A
37 30 14 addcomd φ B - A + A = A + B - A
38 12 eqcomd φ B A = T
39 38 oveq2d φ A + B - A = A + T
40 37 39 eqtrd φ B - A + A = A + T
41 34 36 40 3eqtrd φ B + B A - B A = A + T
42 29 33 41 3eqtrd φ B = A + T
43 42 adantr φ x B = A + T
44 43 oveq1d φ x B x = A + T - x
45 14 adantr φ x A
46 11 recnd φ x T
47 6 recnd φ x x
48 45 46 47 addsubd φ x A + T - x = A - x + T
49 44 48 eqtrd φ x B x = A - x + T
50 49 oveq1d φ x B x T = A - x + T T
51 45 47 subcld φ x A x
52 51 46 46 18 divdird φ x A - x + T T = A x T + T T
53 4 30 eqeltrid φ T
54 53 17 dividd φ T T = 1
55 54 adantr φ x T T = 1
56 55 oveq2d φ x A x T + T T = A x T + 1
57 50 52 56 3eqtrd φ x B x T = A x T + 1
58 57 fveq2d φ x B x T = A x T + 1
59 58 oveq1d φ x B x T T = A x T + 1 T
60 59 22 eqeltrrd φ x A x T + 1 T
61 peano2re A x T A x T + 1
62 26 61 syl φ x A x T + 1
63 reflcl A x T + 1 A x T + 1
64 62 63 syl φ x A x T + 1
65 1 2 posdifd φ A < B 0 < B A
66 3 65 mpbid φ 0 < B A
67 66 12 breqtrrd φ 0 < T
68 10 67 elrpd φ T +
69 68 adantr φ x T +
70 flltp1 A x T A x T < A x T + 1
71 26 70 syl φ x A x T < A x T + 1
72 1zzd φ x 1
73 fladdz A x T 1 A x T + 1 = A x T + 1
74 26 72 73 syl2anc φ x A x T + 1 = A x T + 1
75 71 74 breqtrrd φ x A x T < A x T + 1
76 26 64 69 75 ltmul1dd φ x A x T T < A x T + 1 T
77 27 60 6 76 ltadd2dd φ x x + A x T T < x + A x T + 1 T
78 51 46 18 divcan1d φ x A x T T = A x
79 78 oveq2d φ x x + A x T T = x + A - x
80 47 45 pncan3d φ x x + A - x = A
81 79 80 eqtrd φ x x + A x T T = A
82 59 oveq2d φ x x + B x T T = x + A x T + 1 T
83 82 eqcomd φ x x + A x T + 1 T = x + B x T T
84 77 81 83 3brtr3d φ x A < x + B x T T
85 19 11 remulcld φ x B x T T
86 flle B x T B x T B x T
87 19 86 syl φ x B x T B x T
88 21 19 69 lemul1d φ x B x T B x T B x T T B x T T
89 87 88 mpbid φ x B x T T B x T T
90 22 85 6 89 leadd2dd φ x x + B x T T x + B x T T
91 8 recnd φ x B x
92 91 46 18 divcan1d φ x B x T T = B x
93 92 oveq2d φ x x + B x T T = x + B - x
94 13 adantr φ x B
95 47 94 pncan3d φ x x + B - x = B
96 93 95 eqtrd φ x x + B x T T = B
97 90 96 breqtrd φ x x + B x T T B
98 24 rexrd φ x A *
99 elioc2 A * B x + B x T T A B x + B x T T A < x + B x T T x + B x T T B
100 98 7 99 syl2anc φ x x + B x T T A B x + B x T T A < x + B x T T x + B x T T B
101 23 84 97 100 mpbir3and φ x x + B x T T A B
102 101 5 fmptd φ E : A B