Metamath Proof Explorer


Theorem fourierdlem82

Description: Integral by substitution, adding a constant to the function's argument, for a function on an open interval with finite limits ad boundary points. (Contributed by Glauco Siliprandi, 11-Dec-2019)

Ref Expression
Hypotheses fourierdlem82.1 G = x A B if x = A R if x = B L F A B x
fourierdlem82.2 φ A
fourierdlem82.3 φ B
fourierdlem82.4 φ A < B
fourierdlem82.5 φ F : A B
fourierdlem82.6 φ F A B : A B cn
fourierdlem82.7 φ L F lim B
fourierdlem82.8 φ R F lim A
fourierdlem82.9 φ X
Assertion fourierdlem82 φ A B F t dt = A X B X F X + t dt

Proof

Step Hyp Ref Expression
1 fourierdlem82.1 G = x A B if x = A R if x = B L F A B x
2 fourierdlem82.2 φ A
3 fourierdlem82.3 φ B
4 fourierdlem82.4 φ A < B
5 fourierdlem82.5 φ F : A B
6 fourierdlem82.6 φ F A B : A B cn
7 fourierdlem82.7 φ L F lim B
8 fourierdlem82.8 φ R F lim A
9 fourierdlem82.9 φ X
10 2 3 4 ltled φ A B
11 2 3 9 10 lesub1dd φ A X B X
12 11 ditgpos φ A X B X G X + t dt = A X B X G X + t dt
13 iftrue x = A if x = A R if x = B L F A B x = R
14 13 adantl φ x = A if x = A R if x = B L F A B x = R
15 iftrue x = A if x = A R if x = B L F x = R
16 15 adantl φ x = A if x = A R if x = B L F x = R
17 14 16 eqtr4d φ x = A if x = A R if x = B L F A B x = if x = A R if x = B L F x
18 17 adantlr φ x A B x = A if x = A R if x = B L F A B x = if x = A R if x = B L F x
19 iffalse ¬ x = A if x = A R if x = B L F A B x = if x = B L F A B x
20 iftrue x = B if x = B L F A B x = L
21 19 20 sylan9eq ¬ x = A x = B if x = A R if x = B L F A B x = L
22 21 adantll φ x A B ¬ x = A x = B if x = A R if x = B L F A B x = L
23 iffalse ¬ x = A if x = A R if x = B L F x = if x = B L F x
24 iftrue x = B if x = B L F x = L
25 23 24 sylan9eq ¬ x = A x = B if x = A R if x = B L F x = L
26 25 adantll φ x A B ¬ x = A x = B if x = A R if x = B L F x = L
27 22 26 eqtr4d φ x A B ¬ x = A x = B if x = A R if x = B L F A B x = if x = A R if x = B L F x
28 iffalse ¬ x = B if x = B L F A B x = F A B x
29 28 adantl φ x A B ¬ x = A ¬ x = B if x = B L F A B x = F A B x
30 19 ad2antlr φ x A B ¬ x = A ¬ x = B if x = A R if x = B L F A B x = if x = B L F A B x
31 iffalse ¬ x = B if x = B L F x = F x
32 31 adantl φ x A B ¬ x = A ¬ x = B if x = B L F x = F x
33 23 ad2antlr φ x A B ¬ x = A ¬ x = B if x = A R if x = B L F x = if x = B L F x
34 2 rexrd φ A *
35 34 ad3antrrr φ x A B ¬ x = A ¬ x = B A *
36 3 rexrd φ B *
37 36 ad3antrrr φ x A B ¬ x = A ¬ x = B B *
38 2 adantr φ x A B A
39 3 adantr φ x A B B
40 simpr φ x A B x A B
41 eliccre A B x A B x
42 38 39 40 41 syl3anc φ x A B x
43 42 ad2antrr φ x A B ¬ x = A ¬ x = B x
44 2 ad2antrr φ x A B ¬ x = A A
45 42 adantr φ x A B ¬ x = A x
46 elicc2 A B x A B x A x x B
47 38 39 46 syl2anc φ x A B x A B x A x x B
48 40 47 mpbid φ x A B x A x x B
49 48 simp2d φ x A B A x
50 49 adantr φ x A B ¬ x = A A x
51 neqne ¬ x = A x A
52 51 adantl φ x A B ¬ x = A x A
53 44 45 50 52 leneltd φ x A B ¬ x = A A < x
54 53 adantr φ x A B ¬ x = A ¬ x = B A < x
55 42 adantr φ x A B ¬ x = B x
56 3 ad2antrr φ x A B ¬ x = B B
57 48 simp3d φ x A B x B
58 57 adantr φ x A B ¬ x = B x B
59 nesym B x ¬ x = B
60 59 biimpri ¬ x = B B x
61 60 adantl φ x A B ¬ x = B B x
62 55 56 58 61 leneltd φ x A B ¬ x = B x < B
63 62 adantlr φ x A B ¬ x = A ¬ x = B x < B
64 35 37 43 54 63 eliood φ x A B ¬ x = A ¬ x = B x A B
65 fvres x A B F A B x = F x
66 64 65 syl φ x A B ¬ x = A ¬ x = B F A B x = F x
67 32 33 66 3eqtr4d φ x A B ¬ x = A ¬ x = B if x = A R if x = B L F x = F A B x
68 29 30 67 3eqtr4d φ x A B ¬ x = A ¬ x = B if x = A R if x = B L F A B x = if x = A R if x = B L F x
69 27 68 pm2.61dan φ x A B ¬ x = A if x = A R if x = B L F A B x = if x = A R if x = B L F x
70 18 69 pm2.61dan φ x A B if x = A R if x = B L F A B x = if x = A R if x = B L F x
71 70 mpteq2dva φ x A B if x = A R if x = B L F A B x = x A B if x = A R if x = B L F x
72 1 71 syl5eq φ G = x A B if x = A R if x = B L F x
73 72 adantr φ t A X B X G = x A B if x = A R if x = B L F x
74 eqeq1 x = X + t x = A X + t = A
75 eqeq1 x = X + t x = B X + t = B
76 fveq2 x = X + t F x = F X + t
77 75 76 ifbieq2d x = X + t if x = B L F x = if X + t = B L F X + t
78 74 77 ifbieq2d x = X + t if x = A R if x = B L F x = if X + t = A R if X + t = B L F X + t
79 2 adantr φ t A X B X A
80 simpr φ t A X B X t A X B X
81 2 9 resubcld φ A X
82 81 rexrd φ A X *
83 82 adantr φ t A X B X A X *
84 3 9 resubcld φ B X
85 84 rexrd φ B X *
86 85 adantr φ t A X B X B X *
87 elioo2 A X * B X * t A X B X t A X < t t < B X
88 83 86 87 syl2anc φ t A X B X t A X B X t A X < t t < B X
89 80 88 mpbid φ t A X B X t A X < t t < B X
90 89 simp2d φ t A X B X A X < t
91 9 adantr φ t A X B X X
92 89 simp1d φ t A X B X t
93 79 91 92 ltsubadd2d φ t A X B X A X < t A < X + t
94 90 93 mpbid φ t A X B X A < X + t
95 79 94 gtned φ t A X B X X + t A
96 95 neneqd φ t A X B X ¬ X + t = A
97 96 iffalsed φ t A X B X if X + t = A R if X + t = B L F X + t = if X + t = B L F X + t
98 91 92 readdcld φ t A X B X X + t
99 89 simp3d φ t A X B X t < B X
100 3 adantr φ t A X B X B
101 91 92 100 ltaddsub2d φ t A X B X X + t < B t < B X
102 99 101 mpbird φ t A X B X X + t < B
103 98 102 ltned φ t A X B X X + t B
104 103 neneqd φ t A X B X ¬ X + t = B
105 104 iffalsed φ t A X B X if X + t = B L F X + t = F X + t
106 97 105 eqtrd φ t A X B X if X + t = A R if X + t = B L F X + t = F X + t
107 78 106 sylan9eqr φ t A X B X x = X + t if x = A R if x = B L F x = F X + t
108 79 98 94 ltled φ t A X B X A X + t
109 98 100 102 ltled φ t A X B X X + t B
110 79 100 98 108 109 eliccd φ t A X B X X + t A B
111 5 ffund φ Fun F
112 111 adantr φ t A X B X Fun F
113 5 fdmd φ dom F = A B
114 113 eqcomd φ A B = dom F
115 114 adantr φ t A X B X A B = dom F
116 110 115 eleqtrd φ t A X B X X + t dom F
117 fvelrn Fun F X + t dom F F X + t ran F
118 112 116 117 syl2anc φ t A X B X F X + t ran F
119 73 107 110 118 fvmptd φ t A X B X G X + t = F X + t
120 119 itgeq2dv φ A X B X G X + t dt = A X B X F X + t dt
121 5 frnd φ ran F
122 121 adantr φ t A X B X ran F
123 111 adantr φ t A X B X Fun F
124 2 adantr φ t A X B X A
125 3 adantr φ t A X B X B
126 9 adantr φ t A X B X X
127 81 adantr φ t A X B X A X
128 84 adantr φ t A X B X B X
129 simpr φ t A X B X t A X B X
130 eliccre A X B X t A X B X t
131 127 128 129 130 syl3anc φ t A X B X t
132 126 131 readdcld φ t A X B X X + t
133 elicc2 A X B X t A X B X t A X t t B X
134 127 128 133 syl2anc φ t A X B X t A X B X t A X t t B X
135 129 134 mpbid φ t A X B X t A X t t B X
136 135 simp2d φ t A X B X A X t
137 124 126 131 lesubadd2d φ t A X B X A X t A X + t
138 136 137 mpbid φ t A X B X A X + t
139 135 simp3d φ t A X B X t B X
140 126 131 125 leaddsub2d φ t A X B X X + t B t B X
141 139 140 mpbird φ t A X B X X + t B
142 124 125 132 138 141 eliccd φ t A X B X X + t A B
143 114 adantr φ t A X B X A B = dom F
144 142 143 eleqtrd φ t A X B X X + t dom F
145 123 144 117 syl2anc φ t A X B X F X + t ran F
146 122 145 sseldd φ t A X B X F X + t
147 81 84 146 itgioo φ A X B X F X + t dt = A X B X F X + t dt
148 12 120 147 3eqtrrd φ A X B X F X + t dt = A X B X G X + t dt
149 nfv x φ
150 2 3 4 5 limcicciooub φ F A B lim B = F lim B
151 7 150 eleqtrrd φ L F A B lim B
152 2 3 4 5 limciccioolb φ F A B lim A = F lim A
153 8 152 eleqtrrd φ R F A B lim A
154 149 1 2 3 6 151 153 cncfiooicc φ G : A B cn
155 2 3 10 9 154 itgsbtaddcnst φ A X B X G X + t dt = A B G s ds
156 10 ditgpos φ A B G s ds = A B G s ds
157 fveq2 s = t G s = G t
158 157 cbvitgv A B G s ds = A B G t dt
159 1 a1i φ t A B G = x A B if x = A R if x = B L F A B x
160 2 ad2antrr φ t A B x = t A
161 simplr φ t A B x = t t A B
162 34 ad2antrr φ t A B x = t A *
163 36 ad2antrr φ t A B x = t B *
164 elioo2 A * B * t A B t A < t t < B
165 162 163 164 syl2anc φ t A B x = t t A B t A < t t < B
166 161 165 mpbid φ t A B x = t t A < t t < B
167 166 simp2d φ t A B x = t A < t
168 simpr φ t A B x = t x = t
169 167 168 breqtrrd φ t A B x = t A < x
170 160 169 gtned φ t A B x = t x A
171 170 neneqd φ t A B x = t ¬ x = A
172 171 iffalsed φ t A B x = t if x = A R if x = B L F A B x = if x = B L F A B x
173 166 simp1d φ t A B x = t t
174 168 173 eqeltrd φ t A B x = t x
175 166 simp3d φ t A B x = t t < B
176 168 175 eqbrtrd φ t A B x = t x < B
177 174 176 ltned φ t A B x = t x B
178 177 neneqd φ t A B x = t ¬ x = B
179 178 iffalsed φ t A B x = t if x = B L F A B x = F A B x
180 168 161 eqeltrd φ t A B x = t x A B
181 180 65 syl φ t A B x = t F A B x = F x
182 fveq2 x = t F x = F t
183 182 adantl φ t A B x = t F x = F t
184 181 183 eqtrd φ t A B x = t F A B x = F t
185 172 179 184 3eqtrd φ t A B x = t if x = A R if x = B L F A B x = F t
186 ioossicc A B A B
187 simpr φ t A B t A B
188 186 187 sseldi φ t A B t A B
189 111 adantr φ t A B Fun F
190 114 adantr φ t A B A B = dom F
191 188 190 eleqtrd φ t A B t dom F
192 fvelrn Fun F t dom F F t ran F
193 189 191 192 syl2anc φ t A B F t ran F
194 159 185 188 193 fvmptd φ t A B G t = F t
195 194 itgeq2dv φ A B G t dt = A B F t dt
196 158 195 syl5eq φ A B G s ds = A B F t dt
197 5 ffvelrnda φ t A B F t
198 2 3 197 itgioo φ A B F t dt = A B F t dt
199 156 196 198 3eqtrd φ A B G s ds = A B F t dt
200 148 155 199 3eqtrrd φ A B F t dt = A X B X F X + t dt