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=nxifxmod2π=02n+12πsinn+12x2πsinx2
dirkeritg.n φN
dirkeritg.f F=DN
dirkeritg.a φA
dirkeritg.b φB
dirkeritg.aleb φAB
dirkeritg.g G=xABx2+k=1Nsinkxkπ
Assertion dirkeritg φABFxdx=GBGA

Proof

Step Hyp Ref Expression
1 dirkeritg.d D=nxifxmod2π=02n+12πsinn+12x2πsinx2
2 dirkeritg.n φN
3 dirkeritg.f F=DN
4 dirkeritg.a φA
5 dirkeritg.b φB
6 dirkeritg.aleb φAB
7 dirkeritg.g G=xABx2+k=1Nsinkxkπ
8 fveq2 x=sFx=Fs
9 8 cbvitgv ABFxdx=ABFsds
10 9 a1i φABFxdx=ABFsds
11 elioore sABs
12 11 adantl φsABs
13 halfre 12
14 13 a1i s12
15 fzfid s1NFin
16 elfzelz k1Nk
17 16 zred k1Nk
18 17 adantl sk1Nk
19 simpl sk1Ns
20 18 19 remulcld sk1Nks
21 20 recoscld sk1Ncosks
22 15 21 fsumrecl sk=1Ncosks
23 14 22 readdcld s12+k=1Ncosks
24 pire π
25 24 a1i sπ
26 pipos 0<π
27 24 26 gt0ne0ii π0
28 27 a1i sπ0
29 23 25 28 redivcld s12+k=1Ncosksπ
30 12 29 syl φsAB12+k=1Ncosksπ
31 eqid s12+k=1Ncosksπ=s12+k=1Ncosksπ
32 31 fvmpt2 s12+k=1Ncosksπs12+k=1Ncosksπs=12+k=1Ncosksπ
33 12 30 32 syl2anc φsABs12+k=1Ncosksπs=12+k=1Ncosksπ
34 oveq1 x=sxmod2π=smod2π
35 34 eqeq1d x=sxmod2π=0smod2π=0
36 oveq2 x=sn+12x=n+12s
37 36 fveq2d x=ssinn+12x=sinn+12s
38 oveq1 x=sx2=s2
39 38 fveq2d x=ssinx2=sins2
40 39 oveq2d x=s2πsinx2=2πsins2
41 37 40 oveq12d x=ssinn+12x2πsinx2=sinn+12s2πsins2
42 35 41 ifbieq2d x=sifxmod2π=02n+12πsinn+12x2πsinx2=ifsmod2π=02n+12πsinn+12s2πsins2
43 42 cbvmptv xifxmod2π=02n+12πsinn+12x2πsinx2=sifsmod2π=02n+12πsinn+12s2πsins2
44 43 mpteq2i nxifxmod2π=02n+12πsinn+12x2πsinx2=nsifsmod2π=02n+12πsinn+12s2πsins2
45 1 44 eqtri D=nsifsmod2π=02n+12πsinn+12s2πsins2
46 45 2 3 31 dirkertrigeq φF=s12+k=1Ncosksπ
47 46 fveq1d φFs=s12+k=1Ncosksπs
48 47 adantr φsABFs=s12+k=1Ncosksπs
49 oveq2 x=skx=ks
50 49 fveq2d x=ssinkx=sinks
51 50 oveq1d x=ssinkxk=sinksk
52 51 sumeq2sdv x=sk=1Nsinkxk=k=1Nsinksk
53 38 52 oveq12d x=sx2+k=1Nsinkxk=s2+k=1Nsinksk
54 53 oveq1d x=sx2+k=1Nsinkxkπ=s2+k=1Nsinkskπ
55 54 cbvmptv xABx2+k=1Nsinkxkπ=sABs2+k=1Nsinkskπ
56 7 55 eqtri G=sABs2+k=1Nsinkskπ
57 56 oveq2i DG=dsABs2+k=1Nsinkskπds
58 reelprrecn
59 58 a1i φ
60 recn ss
61 60 halfcld ss2
62 16 zcnd k1Nk
63 62 adantl sk1Nk
64 60 adantr sk1Ns
65 63 64 mulcld sk1Nks
66 65 sincld sk1Nsinks
67 0red k1N0
68 1red k1N1
69 0lt1 0<1
70 69 a1i k1N0<1
71 elfzle1 k1N1k
72 67 68 17 70 71 ltletrd k1N0<k
73 72 gt0ne0d k1Nk0
74 73 adantl sk1Nk0
75 66 63 74 divcld sk1Nsinksk
76 15 75 fsumcl sk=1Nsinksk
77 61 76 addcld ss2+k=1Nsinksk
78 picn π
79 78 a1i sπ
80 77 79 28 divcld ss2+k=1Nsinkskπ
81 80 adantl φss2+k=1Nsinkskπ
82 29 adantl φs12+k=1Ncosksπ
83 77 adantl φss2+k=1Nsinksk
84 23 adantl φs12+k=1Ncosks
85 61 adantl φss2
86 13 a1i φs12
87 60 adantl φss
88 1red φs1
89 59 dvmptid φdssds=s1
90 2cnd φ2
91 2ne0 20
92 91 a1i φ20
93 59 87 88 89 90 92 dvmptdivc φdss2ds=s12
94 76 adantl φsk=1Nsinksk
95 22 adantl φsk=1Ncosks
96 eqid TopOpenfld=TopOpenfld
97 96 tgioo2 topGenran.=TopOpenfld𝑡
98 reopn topGenran.
99 98 a1i φtopGenran.
100 fzfid φ1NFin
101 75 ancoms k1Nssinksk
102 101 3adant1 φk1Nssinksk
103 21 ancoms k1Nscosks
104 103 recnd k1Nscosks
105 104 3adant1 φk1Nscosks
106 58 a1i k1N
107 66 ancoms k1Nssinks
108 62 adantr k1Nsk
109 simpr k1Nss
110 108 109 mulcld k1Nsks
111 110 coscld k1Nscosks
112 108 111 mulcld k1Nskcosks
113 60 112 sylan2 k1Nskcosks
114 ax-resscn
115 resmpt ssinks=ssinks
116 114 115 mp1i k1Nssinks=ssinks
117 116 eqcomd k1Nssinks=ssinks
118 117 oveq2d k1Ndssinksds=Dssinks
119 110 sincld k1Nssinks
120 119 fmpttd k1Nssinks:
121 112 ralrimiva k1Nskcosks
122 dmmptg skcosksdomskcosks=
123 121 122 syl k1Ndomskcosks=
124 114 123 sseqtrrid k1Ndomskcosks
125 dvsinax kdssinksds=skcosks
126 62 125 syl k1Ndssinksds=skcosks
127 126 dmeqd k1Ndomdssinksds=domskcosks
128 124 127 sseqtrrd k1Ndomdssinksds
129 dvcnre ssinks:domdssinksdsDssinks=dssinksds
130 120 128 129 syl2anc k1NDssinks=dssinksds
131 126 reseq1d k1Ndssinksds=skcosks
132 resmpt skcosks=skcosks
133 114 132 ax-mp skcosks=skcosks
134 131 133 eqtrdi k1Ndssinksds=skcosks
135 118 130 134 3eqtrd k1Ndssinksds=skcosks
136 106 107 113 135 62 73 dvmptdivc k1Ndssinkskds=skcosksk
137 62 adantr k1Nsk
138 73 adantr k1Nsk0
139 104 137 138 divcan3d k1Nskcosksk=cosks
140 139 mpteq2dva k1Nskcosksk=scosks
141 136 140 eqtrd k1Ndssinkskds=scosks
142 141 adantl φk1Ndssinkskds=scosks
143 97 96 59 99 100 102 105 142 dvmptfsum φdsk=1Nsinkskds=sk=1Ncosks
144 59 85 86 93 94 95 143 dvmptadd φdss2+k=1Nsinkskds=s12+k=1Ncosks
145 78 a1i φπ
146 27 a1i φπ0
147 59 83 84 144 145 146 dvmptdivc φdss2+k=1Nsinkskπds=s12+k=1Ncosksπ
148 4 5 iccssred φAB
149 iccntr ABinttopGenran.AB=AB
150 4 5 149 syl2anc φinttopGenran.AB=AB
151 59 81 82 147 148 97 96 150 dvmptres2 φdsABs2+k=1Nsinkskπds=sAB12+k=1Ncosksπ
152 57 151 eqtrid φDG=sAB12+k=1Ncosksπ
153 152 30 fvmpt2d φsABGs=12+k=1Ncosksπ
154 33 48 153 3eqtr4d φsABFs=Gs
155 154 itgeq2dv φABFsds=ABGsds
156 ioosscn AB
157 156 a1i φAB
158 halfcn 12
159 158 a1i φ12
160 ssid
161 160 a1i φ
162 157 159 161 constcncfg φsAB12:ABcn
163 eqid scosks=scosks
164 coscn cos:cn
165 164 a1i k1Ncos:cn
166 eqid sks=sks
167 166 mulc1cncf ksks:cn
168 62 167 syl k1Nsks:cn
169 165 168 cncfmpt1f k1Nscosks:cn
170 156 a1i k1NAB
171 160 a1i k1N
172 11 104 sylan2 k1NsABcosks
173 163 169 170 171 172 cncfmptssg k1NsABcosks:ABcn
174 173 adantl φk1NsABcosks:ABcn
175 157 100 174 fsumcncf φsABk=1Ncosks:ABcn
176 162 175 addcncf φsAB12+k=1Ncosks:ABcn
177 eqid sπ=sπ
178 cncfmptc πsπ:cn
179 78 160 160 178 mp3an sπ:cn
180 179 a1i φsπ:cn
181 difssd φ0
182 eldifsn π0ππ0
183 78 27 182 mpbir2an π0
184 183 a1i φsABπ0
185 177 180 157 181 184 cncfmptssg φsABπ:ABcn0
186 176 185 divcncf φsAB12+k=1Ncosksπ:ABcn
187 152 186 eqeltrd φG:ABcn
188 ioossicc ABAB
189 188 a1i φABAB
190 ioombl ABdomvol
191 190 a1i φABdomvol
192 13 a1i φsAB12
193 fzfid φsAB1NFin
194 17 adantl φsABk1Nk
195 148 sselda φsABs
196 195 adantr φsABk1Ns
197 194 196 remulcld φsABk1Nks
198 197 recoscld φsABk1Ncosks
199 193 198 fsumrecl φsABk=1Ncosks
200 192 199 readdcld φsAB12+k=1Ncosks
201 24 a1i φsABπ
202 27 a1i φsABπ0
203 200 201 202 redivcld φsAB12+k=1Ncosksπ
204 148 114 sstrdi φAB
205 204 159 161 constcncfg φsAB12:ABcn
206 eqid sk=1Ncosks=sk=1Ncosks
207 169 adantl φk1Nscosks:cn
208 161 100 207 fsumcncf φsk=1Ncosks:cn
209 199 recnd φsABk=1Ncosks
210 206 208 204 161 209 cncfmptssg φsABk=1Ncosks:ABcn
211 205 210 addcncf φsAB12+k=1Ncosks:ABcn
212 183 a1i φπ0
213 204 212 181 constcncfg φsABπ:ABcn0
214 211 213 divcncf φsAB12+k=1Ncosksπ:ABcn
215 cniccibl ABsAB12+k=1Ncosksπ:ABcnsAB12+k=1Ncosksπ𝐿1
216 4 5 214 215 syl3anc φsAB12+k=1Ncosksπ𝐿1
217 189 191 203 216 iblss φsAB12+k=1Ncosksπ𝐿1
218 152 217 eqeltrd φDG𝐿1
219 204 161 idcncfg φsABs:ABcn
220 2cn 2
221 eldifsn 20220
222 220 91 221 mpbir2an 20
223 222 a1i φ20
224 204 223 181 constcncfg φsAB2:ABcn0
225 219 224 divcncf φsABs2:ABcn
226 eqid ssinks=ssinks
227 sincn sin:cn
228 227 a1i k1Nsin:cn
229 228 168 cncfmpt1f k1Nssinks:cn
230 229 adantl φk1Nssinks:cn
231 204 adantr φk1NAB
232 160 a1i φk1N
233 62 ad2antlr φk1NsABk
234 195 recnd φsABs
235 234 adantlr φk1NsABs
236 233 235 mulcld φk1NsABks
237 236 sincld φk1NsABsinks
238 226 230 231 232 237 cncfmptssg φk1NsABsinks:ABcn
239 eldifsn k0kk0
240 62 73 239 sylanbrc k1Nk0
241 240 adantl φk1Nk0
242 difssd φk1N0
243 231 241 242 constcncfg φk1NsABk:ABcn0
244 238 243 divcncf φk1NsABsinksk:ABcn
245 204 100 244 fsumcncf φsABk=1Nsinksk:ABcn
246 225 245 addcncf φsABs2+k=1Nsinksk:ABcn
247 246 213 divcncf φsABs2+k=1Nsinkskπ:ABcn
248 56 247 eqeltrid φG:ABcn
249 4 5 6 187 218 248 ftc2 φABGsds=GBGA
250 10 155 249 3eqtrd φABFxdx=GBGA