Metamath Proof Explorer


Theorem dirkeritg

Description: The definite integral of the Dirichlet Kernel. (Contributed by Glauco Siliprandi, 11-Dec-2019)

Ref Expression
Hypotheses dirkeritg.d D = n x if x mod 2 π = 0 2 n + 1 2 π sin n + 1 2 x 2 π sin x 2
dirkeritg.n φ N
dirkeritg.f F = D N
dirkeritg.a φ A
dirkeritg.b φ B
dirkeritg.aleb φ A B
dirkeritg.g G = x A B x 2 + k = 1 N sin k x k π
Assertion dirkeritg φ A B F x dx = G B G A

Proof

Step Hyp Ref Expression
1 dirkeritg.d D = n x if x mod 2 π = 0 2 n + 1 2 π sin n + 1 2 x 2 π sin x 2
2 dirkeritg.n φ N
3 dirkeritg.f F = D N
4 dirkeritg.a φ A
5 dirkeritg.b φ B
6 dirkeritg.aleb φ A B
7 dirkeritg.g G = x A B x 2 + k = 1 N sin k x k π
8 fveq2 x = s F x = F s
9 8 cbvitgv A B F x dx = A B F s ds
10 9 a1i φ A B F x dx = A B F s ds
11 elioore s A B s
12 11 adantl φ s A B s
13 halfre 1 2
14 13 a1i s 1 2
15 fzfid s 1 N Fin
16 elfzelz k 1 N k
17 16 zred k 1 N k
18 17 adantl s k 1 N k
19 simpl s k 1 N s
20 18 19 remulcld s k 1 N k s
21 20 recoscld s k 1 N cos k s
22 15 21 fsumrecl s k = 1 N cos k s
23 14 22 readdcld s 1 2 + k = 1 N cos k s
24 pire π
25 24 a1i s π
26 pipos 0 < π
27 24 26 gt0ne0ii π 0
28 27 a1i s π 0
29 23 25 28 redivcld s 1 2 + k = 1 N cos k s π
30 12 29 syl φ s A B 1 2 + k = 1 N cos k s π
31 eqid s 1 2 + k = 1 N cos k s π = s 1 2 + k = 1 N cos k s π
32 31 fvmpt2 s 1 2 + k = 1 N cos k s π s 1 2 + k = 1 N cos k s π s = 1 2 + k = 1 N cos k s π
33 12 30 32 syl2anc φ s A B s 1 2 + k = 1 N cos k s π s = 1 2 + k = 1 N cos k s π
34 oveq1 x = s x mod 2 π = s mod 2 π
35 34 eqeq1d x = s x mod 2 π = 0 s mod 2 π = 0
36 oveq2 x = s n + 1 2 x = n + 1 2 s
37 36 fveq2d x = s sin n + 1 2 x = sin n + 1 2 s
38 oveq1 x = s x 2 = s 2
39 38 fveq2d x = s sin x 2 = sin s 2
40 39 oveq2d x = s 2 π sin x 2 = 2 π sin s 2
41 37 40 oveq12d x = s sin n + 1 2 x 2 π sin x 2 = sin n + 1 2 s 2 π sin s 2
42 35 41 ifbieq2d x = s if x mod 2 π = 0 2 n + 1 2 π sin n + 1 2 x 2 π sin x 2 = if s mod 2 π = 0 2 n + 1 2 π sin n + 1 2 s 2 π sin s 2
43 42 cbvmptv x if x mod 2 π = 0 2 n + 1 2 π sin n + 1 2 x 2 π sin x 2 = s if s mod 2 π = 0 2 n + 1 2 π sin n + 1 2 s 2 π sin s 2
44 43 mpteq2i n x if x mod 2 π = 0 2 n + 1 2 π sin n + 1 2 x 2 π sin x 2 = n s if s mod 2 π = 0 2 n + 1 2 π sin n + 1 2 s 2 π sin s 2
45 1 44 eqtri D = n s if s mod 2 π = 0 2 n + 1 2 π sin n + 1 2 s 2 π sin s 2
46 45 2 3 31 dirkertrigeq φ F = s 1 2 + k = 1 N cos k s π
47 46 fveq1d φ F s = s 1 2 + k = 1 N cos k s π s
48 47 adantr φ s A B F s = s 1 2 + k = 1 N cos k s π s
49 oveq2 x = s k x = k s
50 49 fveq2d x = s sin k x = sin k s
51 50 oveq1d x = s sin k x k = sin k s k
52 51 sumeq2sdv x = s k = 1 N sin k x k = k = 1 N sin k s k
53 38 52 oveq12d x = s x 2 + k = 1 N sin k x k = s 2 + k = 1 N sin k s k
54 53 oveq1d x = s x 2 + k = 1 N sin k x k π = s 2 + k = 1 N sin k s k π
55 54 cbvmptv x A B x 2 + k = 1 N sin k x k π = s A B s 2 + k = 1 N sin k s k π
56 7 55 eqtri G = s A B s 2 + k = 1 N sin k s k π
57 56 oveq2i D G = ds A B s 2 + k = 1 N sin k s k π d s
58 reelprrecn
59 58 a1i φ
60 recn s s
61 60 halfcld s s 2
62 16 zcnd k 1 N k
63 62 adantl s k 1 N k
64 60 adantr s k 1 N s
65 63 64 mulcld s k 1 N k s
66 65 sincld s k 1 N sin k s
67 0red k 1 N 0
68 1red k 1 N 1
69 0lt1 0 < 1
70 69 a1i k 1 N 0 < 1
71 elfzle1 k 1 N 1 k
72 67 68 17 70 71 ltletrd k 1 N 0 < k
73 72 gt0ne0d k 1 N k 0
74 73 adantl s k 1 N k 0
75 66 63 74 divcld s k 1 N sin k s k
76 15 75 fsumcl s k = 1 N sin k s k
77 61 76 addcld s s 2 + k = 1 N sin k s k
78 picn π
79 78 a1i s π
80 77 79 28 divcld s s 2 + k = 1 N sin k s k π
81 80 adantl φ s s 2 + k = 1 N sin k s k π
82 29 adantl φ s 1 2 + k = 1 N cos k s π
83 77 adantl φ s s 2 + k = 1 N sin k s k
84 23 adantl φ s 1 2 + k = 1 N cos k s
85 61 adantl φ s s 2
86 13 a1i φ s 1 2
87 60 adantl φ s s
88 1red φ s 1
89 59 dvmptid φ ds s d s = s 1
90 2cnd φ 2
91 2ne0 2 0
92 91 a1i φ 2 0
93 59 87 88 89 90 92 dvmptdivc φ ds s 2 d s = s 1 2
94 76 adantl φ s k = 1 N sin k s k
95 22 adantl φ s k = 1 N cos k s
96 eqid TopOpen fld = TopOpen fld
97 96 tgioo2 topGen ran . = TopOpen fld 𝑡
98 reopn topGen ran .
99 98 a1i φ topGen ran .
100 fzfid φ 1 N Fin
101 75 ancoms k 1 N s sin k s k
102 101 3adant1 φ k 1 N s sin k s k
103 21 ancoms k 1 N s cos k s
104 103 recnd k 1 N s cos k s
105 104 3adant1 φ k 1 N s cos k s
106 58 a1i k 1 N
107 66 ancoms k 1 N s sin k s
108 62 adantr k 1 N s k
109 simpr k 1 N s s
110 108 109 mulcld k 1 N s k s
111 110 coscld k 1 N s cos k s
112 108 111 mulcld k 1 N s k cos k s
113 60 112 sylan2 k 1 N s k cos k s
114 ax-resscn
115 resmpt s sin k s = s sin k s
116 114 115 mp1i k 1 N s sin k s = s sin k s
117 116 eqcomd k 1 N s sin k s = s sin k s
118 117 oveq2d k 1 N ds sin k s d s = D s sin k s
119 110 sincld k 1 N s sin k s
120 119 fmpttd k 1 N s sin k s :
121 112 ralrimiva k 1 N s k cos k s
122 dmmptg s k cos k s dom s k cos k s =
123 121 122 syl k 1 N dom s k cos k s =
124 114 123 sseqtrrid k 1 N dom s k cos k s
125 dvsinax k ds sin k s d s = s k cos k s
126 62 125 syl k 1 N ds sin k s d s = s k cos k s
127 126 dmeqd k 1 N dom ds sin k s d s = dom s k cos k s
128 124 127 sseqtrrd k 1 N dom ds sin k s d s
129 dvcnre s sin k s : dom ds sin k s d s D s sin k s = ds sin k s d s
130 120 128 129 syl2anc k 1 N D s sin k s = ds sin k s d s
131 126 reseq1d k 1 N ds sin k s d s = s k cos k s
132 resmpt s k cos k s = s k cos k s
133 114 132 ax-mp s k cos k s = s k cos k s
134 131 133 eqtrdi k 1 N ds sin k s d s = s k cos k s
135 118 130 134 3eqtrd k 1 N ds sin k s d s = s k cos k s
136 106 107 113 135 62 73 dvmptdivc k 1 N ds sin k s k d s = s k cos k s k
137 62 adantr k 1 N s k
138 73 adantr k 1 N s k 0
139 104 137 138 divcan3d k 1 N s k cos k s k = cos k s
140 139 mpteq2dva k 1 N s k cos k s k = s cos k s
141 136 140 eqtrd k 1 N ds sin k s k d s = s cos k s
142 141 adantl φ k 1 N ds sin k s k d s = s cos k s
143 97 96 59 99 100 102 105 142 dvmptfsum φ ds k = 1 N sin k s k d s = s k = 1 N cos k s
144 59 85 86 93 94 95 143 dvmptadd φ ds s 2 + k = 1 N sin k s k d s = s 1 2 + k = 1 N cos k s
145 78 a1i φ π
146 27 a1i φ π 0
147 59 83 84 144 145 146 dvmptdivc φ ds s 2 + k = 1 N sin k s k π d s = s 1 2 + k = 1 N cos k s π
148 4 5 iccssred φ A B
149 iccntr A B int topGen ran . A B = A B
150 4 5 149 syl2anc φ int topGen ran . A B = A B
151 59 81 82 147 148 97 96 150 dvmptres2 φ ds A B s 2 + k = 1 N sin k s k π d s = s A B 1 2 + k = 1 N cos k s π
152 57 151 syl5eq φ D G = s A B 1 2 + k = 1 N cos k s π
153 152 30 fvmpt2d φ s A B G s = 1 2 + k = 1 N cos k s π
154 33 48 153 3eqtr4d φ s A B F s = G s
155 154 itgeq2dv φ A B F s ds = A B G s ds
156 ioosscn A B
157 156 a1i φ A B
158 halfcn 1 2
159 158 a1i φ 1 2
160 ssid
161 160 a1i φ
162 157 159 161 constcncfg φ s A B 1 2 : A B cn
163 eqid s cos k s = s cos k s
164 coscn cos : cn
165 164 a1i k 1 N cos : cn
166 eqid s k s = s k s
167 166 mulc1cncf k s k s : cn
168 62 167 syl k 1 N s k s : cn
169 165 168 cncfmpt1f k 1 N s cos k s : cn
170 156 a1i k 1 N A B
171 160 a1i k 1 N
172 11 104 sylan2 k 1 N s A B cos k s
173 163 169 170 171 172 cncfmptssg k 1 N s A B cos k s : A B cn
174 173 adantl φ k 1 N s A B cos k s : A B cn
175 157 100 174 fsumcncf φ s A B k = 1 N cos k s : A B cn
176 162 175 addcncf φ s A B 1 2 + k = 1 N cos k s : A B cn
177 eqid s π = s π
178 cncfmptc π s π : cn
179 78 160 160 178 mp3an s π : cn
180 179 a1i φ s π : cn
181 difssd φ 0
182 eldifsn π 0 π π 0
183 78 27 182 mpbir2an π 0
184 183 a1i φ s A B π 0
185 177 180 157 181 184 cncfmptssg φ s A B π : A B cn 0
186 176 185 divcncf φ s A B 1 2 + k = 1 N cos k s π : A B cn
187 152 186 eqeltrd φ G : A B cn
188 ioossicc A B A B
189 188 a1i φ A B A B
190 ioombl A B dom vol
191 190 a1i φ A B dom vol
192 13 a1i φ s A B 1 2
193 fzfid φ s A B 1 N Fin
194 17 adantl φ s A B k 1 N k
195 148 sselda φ s A B s
196 195 adantr φ s A B k 1 N s
197 194 196 remulcld φ s A B k 1 N k s
198 197 recoscld φ s A B k 1 N cos k s
199 193 198 fsumrecl φ s A B k = 1 N cos k s
200 192 199 readdcld φ s A B 1 2 + k = 1 N cos k s
201 24 a1i φ s A B π
202 27 a1i φ s A B π 0
203 200 201 202 redivcld φ s A B 1 2 + k = 1 N cos k s π
204 148 114 sstrdi φ A B
205 204 159 161 constcncfg φ s A B 1 2 : A B cn
206 eqid s k = 1 N cos k s = s k = 1 N cos k s
207 169 adantl φ k 1 N s cos k s : cn
208 161 100 207 fsumcncf φ s k = 1 N cos k s : cn
209 199 recnd φ s A B k = 1 N cos k s
210 206 208 204 161 209 cncfmptssg φ s A B k = 1 N cos k s : A B cn
211 205 210 addcncf φ s A B 1 2 + k = 1 N cos k s : A B cn
212 183 a1i φ π 0
213 204 212 181 constcncfg φ s A B π : A B cn 0
214 211 213 divcncf φ s A B 1 2 + k = 1 N cos k s π : A B cn
215 cniccibl A B s A B 1 2 + k = 1 N cos k s π : A B cn s A B 1 2 + k = 1 N cos k s π 𝐿 1
216 4 5 214 215 syl3anc φ s A B 1 2 + k = 1 N cos k s π 𝐿 1
217 189 191 203 216 iblss φ s A B 1 2 + k = 1 N cos k s π 𝐿 1
218 152 217 eqeltrd φ D G 𝐿 1
219 204 161 idcncfg φ s A B s : A B cn
220 2cn 2
221 eldifsn 2 0 2 2 0
222 220 91 221 mpbir2an 2 0
223 222 a1i φ 2 0
224 204 223 181 constcncfg φ s A B 2 : A B cn 0
225 219 224 divcncf φ s A B s 2 : A B cn
226 eqid s sin k s = s sin k s
227 sincn sin : cn
228 227 a1i k 1 N sin : cn
229 228 168 cncfmpt1f k 1 N s sin k s : cn
230 229 adantl φ k 1 N s sin k s : cn
231 204 adantr φ k 1 N A B
232 160 a1i φ k 1 N
233 62 ad2antlr φ k 1 N s A B k
234 195 recnd φ s A B s
235 234 adantlr φ k 1 N s A B s
236 233 235 mulcld φ k 1 N s A B k s
237 236 sincld φ k 1 N s A B sin k s
238 226 230 231 232 237 cncfmptssg φ k 1 N s A B sin k s : A B cn
239 eldifsn k 0 k k 0
240 62 73 239 sylanbrc k 1 N k 0
241 240 adantl φ k 1 N k 0
242 difssd φ k 1 N 0
243 231 241 242 constcncfg φ k 1 N s A B k : A B cn 0
244 238 243 divcncf φ k 1 N s A B sin k s k : A B cn
245 204 100 244 fsumcncf φ s A B k = 1 N sin k s k : A B cn
246 225 245 addcncf φ s A B s 2 + k = 1 N sin k s k : A B cn
247 246 213 divcncf φ s A B s 2 + k = 1 N sin k s k π : A B cn
248 56 247 eqeltrid φ G : A B cn
249 4 5 6 187 218 248 ftc2 φ A B G s ds = G B G A
250 10 155 249 3eqtrd φ A B F x dx = G B G A