Metamath Proof Explorer


Theorem fourierdlem112

Description: Here abbreviations (local definitions) are introduced to prove the fourier theorem. ( Zm ) is the m_th partial sum of the fourier series. (Contributed by Glauco Siliprandi, 11-Dec-2019)

Ref Expression
Hypotheses fourierdlem112.f φF:
fourierdlem112.d D=myifymod2π=02m+12πsinm+12y2πsiny2
fourierdlem112.p P=np0n|p0=πpn=πi0..^npi<pi+1
fourierdlem112.m φM
fourierdlem112.q φQPM
fourierdlem112.n N=-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1
fourierdlem112.v V=ιf|fIsom<,<0N-π+Xπ+Xy-π+Xπ+X|ky+kTranQ
fourierdlem112.x φX
fourierdlem112.xran φXranV
fourierdlem112.t T=2π
fourierdlem112.fper φxFx+T=Fx
fourierdlem112.fcn φi0..^MFQiQi+1:QiQi+1cn
fourierdlem112.c φi0..^MCFQiQi+1limQi
fourierdlem112.u φi0..^MUFQiQi+1limQi+1
fourierdlem112.fdvcn φi0..^MFQiQi+1:QiQi+1cn
fourierdlem112.e φEF−∞XlimX
fourierdlem112.i φIFX+∞limX
fourierdlem112.l φLF−∞XlimX
fourierdlem112.r φRFX+∞limX
fourierdlem112.a A=n0ππFxcosnxdxπ
fourierdlem112.b B=nππFxsinnxdxπ
fourierdlem112.z Z=mA02+n=1mAncosnX+BnsinnX
fourierdlem112.23 S=nAncosnX+BnsinnX
fourierdlem112.fbd φwtFtw
fourierdlem112.fdvbd φztdomFFtz
fourierdlem112.25 φX
Assertion fourierdlem112 φseq1+SL+R2A02A02+nAncosnX+BnsinnX=L+R2

Proof

Step Hyp Ref Expression
1 fourierdlem112.f φF:
2 fourierdlem112.d D=myifymod2π=02m+12πsinm+12y2πsiny2
3 fourierdlem112.p P=np0n|p0=πpn=πi0..^npi<pi+1
4 fourierdlem112.m φM
5 fourierdlem112.q φQPM
6 fourierdlem112.n N=-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1
7 fourierdlem112.v V=ιf|fIsom<,<0N-π+Xπ+Xy-π+Xπ+X|ky+kTranQ
8 fourierdlem112.x φX
9 fourierdlem112.xran φXranV
10 fourierdlem112.t T=2π
11 fourierdlem112.fper φxFx+T=Fx
12 fourierdlem112.fcn φi0..^MFQiQi+1:QiQi+1cn
13 fourierdlem112.c φi0..^MCFQiQi+1limQi
14 fourierdlem112.u φi0..^MUFQiQi+1limQi+1
15 fourierdlem112.fdvcn φi0..^MFQiQi+1:QiQi+1cn
16 fourierdlem112.e φEF−∞XlimX
17 fourierdlem112.i φIFX+∞limX
18 fourierdlem112.l φLF−∞XlimX
19 fourierdlem112.r φRFX+∞limX
20 fourierdlem112.a A=n0ππFxcosnxdxπ
21 fourierdlem112.b B=nππFxsinnxdxπ
22 fourierdlem112.z Z=mA02+n=1mAncosnX+BnsinnX
23 fourierdlem112.23 S=nAncosnX+BnsinnX
24 fourierdlem112.fbd φwtFtw
25 fourierdlem112.fdvbd φztdomFFtz
26 fourierdlem112.25 φX
27 fveq2 n=jAn=Aj
28 oveq1 n=jnX=jX
29 28 fveq2d n=jcosnX=cosjX
30 27 29 oveq12d n=jAncosnX=AjcosjX
31 fveq2 n=jBn=Bj
32 28 fveq2d n=jsinnX=sinjX
33 31 32 oveq12d n=jBnsinnX=BjsinjX
34 30 33 oveq12d n=jAncosnX+BnsinnX=AjcosjX+BjsinjX
35 34 cbvmptv nAncosnX+BnsinnX=jAjcosjX+BjsinjX
36 23 35 eqtri S=jAjcosjX+BjsinjX
37 seqeq3 S=jAjcosjX+BjsinjXseq1+S=seq1+jAjcosjX+BjsinjX
38 36 37 mp1i φseq1+S=seq1+jAjcosjX+BjsinjX
39 nnuz =1
40 1zzd φ1
41 nfv nφ
42 nfcv _n
43 nfcv _nπ0
44 nfcv _nFX+s
45 nfcv _n×
46 nfcv _nDms
47 44 45 46 nfov _nFX+sDms
48 43 47 nfitg _nπ0FX+sDmsds
49 42 48 nfmpt _nmπ0FX+sDmsds
50 nfcv _n0π
51 50 47 nfitg _n0πFX+sDmsds
52 42 51 nfmpt _nm0πFX+sDmsds
53 nfmpt1 _nn0ππFxcosnxdxπ
54 20 53 nfcxfr _nA
55 nfcv _n0
56 54 55 nffv _nA0
57 nfcv _n÷
58 nfcv _n2
59 56 57 58 nfov _nA02
60 nfcv _n+
61 nfcv _n1m
62 61 nfsum1 _nn=1mAncosnX+BnsinnX
63 59 60 62 nfov _nA02+n=1mAncosnX+BnsinnX
64 42 63 nfmpt _nmA02+n=1mAncosnX+BnsinnX
65 22 64 nfcxfr _nZ
66 eqid np0n|p0=-π+Xpn=π+Xi0..^npi<pi+1=np0n|p0=-π+Xpn=π+Xi0..^npi<pi+1
67 picn π
68 67 2timesi 2π=π+π
69 67 67 subnegi ππ=π+π
70 68 10 69 3eqtr4i T=ππ
71 pire π
72 71 a1i φπ
73 72 renegcld φπ
74 73 26 readdcld φ-π+X
75 72 26 readdcld φπ+X
76 negpilt0 π<0
77 pipos 0<π
78 71 renegcli π
79 0re 0
80 78 79 71 lttri π<00<ππ<π
81 76 77 80 mp2an π<π
82 81 a1i φπ<π
83 73 72 26 82 ltadd1dd φ-π+X<π+X
84 oveq1 y=xy+kT=x+kT
85 84 eleq1d y=xy+kTranQx+kTranQ
86 85 rexbidv y=xky+kTranQkx+kTranQ
87 86 cbvrabv y-π+Xπ+X|ky+kTranQ=x-π+Xπ+X|kx+kTranQ
88 87 uneq2i -π+Xπ+Xy-π+Xπ+X|ky+kTranQ=-π+Xπ+Xx-π+Xπ+X|kx+kTranQ
89 70 3 4 5 74 75 83 66 88 6 7 fourierdlem54 φNVnp0n|p0=-π+Xpn=π+Xi0..^npi<pi+1NVIsom<,<0N-π+Xπ+Xy-π+Xπ+X|ky+kTranQ
90 89 simpld φNVnp0n|p0=-π+Xpn=π+Xi0..^npi<pi+1N
91 90 simpld φN
92 90 simprd φVnp0n|p0=-π+Xpn=π+Xi0..^npi<pi+1N
93 1 adantr φi0..^NF:
94 fveq2 i=jpi=pj
95 oveq1 i=ji+1=j+1
96 95 fveq2d i=jpi+1=pj+1
97 94 96 breq12d i=jpi<pi+1pj<pj+1
98 97 cbvralvw i0..^npi<pi+1j0..^npj<pj+1
99 98 anbi2i p0=πpn=πi0..^npi<pi+1p0=πpn=πj0..^npj<pj+1
100 99 a1i p0np0=πpn=πi0..^npi<pi+1p0=πpn=πj0..^npj<pj+1
101 100 rabbiia p0n|p0=πpn=πi0..^npi<pi+1=p0n|p0=πpn=πj0..^npj<pj+1
102 101 mpteq2i np0n|p0=πpn=πi0..^npi<pi+1=np0n|p0=πpn=πj0..^npj<pj+1
103 3 102 eqtri P=np0n|p0=πpn=πj0..^npj<pj+1
104 4 adantr φi0..^NM
105 5 adantr φi0..^NQPM
106 11 adantlr φi0..^NxFx+T=Fx
107 eleq1w i=ji0..^Mj0..^M
108 107 anbi2d i=jφi0..^Mφj0..^M
109 fveq2 i=jQi=Qj
110 95 fveq2d i=jQi+1=Qj+1
111 109 110 oveq12d i=jQiQi+1=QjQj+1
112 111 reseq2d i=jFQiQi+1=FQjQj+1
113 111 oveq1d i=jQiQi+1cn=QjQj+1cn
114 112 113 eleq12d i=jFQiQi+1:QiQi+1cnFQjQj+1:QjQj+1cn
115 108 114 imbi12d i=jφi0..^MFQiQi+1:QiQi+1cnφj0..^MFQjQj+1:QjQj+1cn
116 115 12 chvarvv φj0..^MFQjQj+1:QjQj+1cn
117 116 adantlr φi0..^Nj0..^MFQjQj+1:QjQj+1cn
118 74 adantr φi0..^N-π+X
119 74 rexrd φ-π+X*
120 pnfxr +∞*
121 120 a1i φ+∞*
122 75 ltpnfd φπ+X<+∞
123 119 121 75 83 122 eliood φπ+X-π+X+∞
124 123 adantr φi0..^Nπ+X-π+X+∞
125 id i0..^Ni0..^N
126 6 oveq2i 0..^N=0..^-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1
127 125 126 eleqtrdi i0..^Ni0..^-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1
128 127 adantl φi0..^Ni0..^-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1
129 6 oveq2i 0N=0-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1
130 isoeq4 0N=0-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1fIsom<,<0N-π+Xπ+Xy-π+Xπ+X|ky+kTranQfIsom<,<0-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1-π+Xπ+Xy-π+Xπ+X|ky+kTranQ
131 129 130 ax-mp fIsom<,<0N-π+Xπ+Xy-π+Xπ+X|ky+kTranQfIsom<,<0-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1-π+Xπ+Xy-π+Xπ+X|ky+kTranQ
132 131 iotabii ιf|fIsom<,<0N-π+Xπ+Xy-π+Xπ+X|ky+kTranQ=ιf|fIsom<,<0-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1-π+Xπ+Xy-π+Xπ+X|ky+kTranQ
133 7 132 eqtri V=ιf|fIsom<,<0-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1-π+Xπ+Xy-π+Xπ+X|ky+kTranQ
134 93 103 70 104 105 106 117 118 124 128 133 fourierdlem98 φi0..^NFViVi+1:ViVi+1cn
135 24 adantr φi0..^NwtFtw
136 nfra1 ttFtw
137 elioore tViVi+1t
138 rspa tFtwtFtw
139 137 138 sylan2 tFtwtViVi+1Ftw
140 139 ex tFtwtViVi+1Ftw
141 136 140 ralrimi tFtwtViVi+1Ftw
142 141 reximi wtFtwwtViVi+1Ftw
143 135 142 syl φi0..^NwtViVi+1Ftw
144 ssid
145 dvfre F:F:domF
146 1 144 145 sylancl φF:domF
147 146 adantr φi0..^NF:domF
148 eqid DF=DF
149 71 a1i φi0..^Nπ
150 78 a1i φi0..^Nπ
151 111 reseq2d i=jFQiQi+1=FQjQj+1
152 151 113 eleq12d i=jFQiQi+1:QiQi+1cnFQjQj+1:QjQj+1cn
153 108 152 imbi12d i=jφi0..^MFQiQi+1:QiQi+1cnφj0..^MFQjQj+1:QjQj+1cn
154 153 15 chvarvv φj0..^MFQjQj+1:QjQj+1cn
155 154 adantlr φi0..^Nj0..^MFQjQj+1:QjQj+1cn
156 73 8 readdcld φ-π+X
157 156 adantr φi0..^N-π+X
158 156 rexrd φ-π+X*
159 72 8 readdcld φπ+X
160 73 72 8 82 ltadd1dd φ-π+X<π+X
161 159 ltpnfd φπ+X<+∞
162 158 121 159 160 161 eliood φπ+X-π+X+∞
163 162 adantr φi0..^Nπ+X-π+X+∞
164 oveq1 k=hkT=hT
165 164 oveq2d k=hy+kT=y+hT
166 165 eleq1d k=hy+kTranQy+hTranQ
167 166 cbvrexvw ky+kTranQhy+hTranQ
168 167 rgenw y-π+Xπ+Xky+kTranQhy+hTranQ
169 rabbi y-π+Xπ+Xky+kTranQhy+hTranQy-π+Xπ+X|ky+kTranQ=y-π+Xπ+X|hy+hTranQ
170 168 169 mpbi y-π+Xπ+X|ky+kTranQ=y-π+Xπ+X|hy+hTranQ
171 170 uneq2i -π+Xπ+Xy-π+Xπ+X|ky+kTranQ=-π+Xπ+Xy-π+Xπ+X|hy+hTranQ
172 isoeq5 -π+Xπ+Xy-π+Xπ+X|ky+kTranQ=-π+Xπ+Xy-π+Xπ+X|hy+hTranQfIsom<,<0-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1-π+Xπ+Xy-π+Xπ+X|ky+kTranQfIsom<,<0-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1-π+Xπ+Xy-π+Xπ+X|hy+hTranQ
173 171 172 ax-mp fIsom<,<0-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1-π+Xπ+Xy-π+Xπ+X|ky+kTranQfIsom<,<0-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1-π+Xπ+Xy-π+Xπ+X|hy+hTranQ
174 173 iotabii ιf|fIsom<,<0-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1-π+Xπ+Xy-π+Xπ+X|ky+kTranQ=ιf|fIsom<,<0-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1-π+Xπ+Xy-π+Xπ+X|hy+hTranQ
175 133 174 eqtri V=ιf|fIsom<,<0-π+Xπ+Xy-π+Xπ+X|ky+kTranQ1-π+Xπ+Xy-π+Xπ+X|hy+hTranQ
176 eleq1w v=uvdomFudomF
177 fveq2 v=uFv=Fu
178 176 177 ifbieq1d v=uifvdomFFv0=ifudomFFu0
179 178 cbvmptv vifvdomFFv0=uifudomFFu0
180 93 148 103 149 150 70 104 105 106 155 157 163 128 175 179 fourierdlem97 φi0..^NFViVi+1:ViVi+1cn
181 cncff FViVi+1:ViVi+1cnFViVi+1:ViVi+1
182 fdm FViVi+1:ViVi+1domFViVi+1=ViVi+1
183 180 181 182 3syl φi0..^NdomFViVi+1=ViVi+1
184 ssdmres ViVi+1domFdomFViVi+1=ViVi+1
185 183 184 sylibr φi0..^NViVi+1domF
186 147 185 fssresd φi0..^NFViVi+1:ViVi+1
187 ax-resscn
188 187 a1i φi0..^N
189 cncfcdm FViVi+1:ViVi+1cnFViVi+1:ViVi+1cnFViVi+1:ViVi+1
190 188 180 189 syl2anc φi0..^NFViVi+1:ViVi+1cnFViVi+1:ViVi+1
191 186 190 mpbird φi0..^NFViVi+1:ViVi+1cn
192 25 adantr φi0..^NztdomFFtz
193 nfv tφi0..^N
194 nfra1 ttdomFFtz
195 193 194 nfan tφi0..^NtdomFFtz
196 fvres tViVi+1FViVi+1t=Ft
197 196 adantl φi0..^NtViVi+1FViVi+1t=Ft
198 197 fveq2d φi0..^NtViVi+1FViVi+1t=Ft
199 198 adantlr φi0..^NtdomFFtztViVi+1FViVi+1t=Ft
200 simplr φi0..^NtdomFFtztViVi+1tdomFFtz
201 185 sselda φi0..^NtViVi+1tdomF
202 201 adantlr φi0..^NtdomFFtztViVi+1tdomF
203 rspa tdomFFtztdomFFtz
204 200 202 203 syl2anc φi0..^NtdomFFtztViVi+1Ftz
205 199 204 eqbrtrd φi0..^NtdomFFtztViVi+1FViVi+1tz
206 205 ex φi0..^NtdomFFtztViVi+1FViVi+1tz
207 195 206 ralrimi φi0..^NtdomFFtztViVi+1FViVi+1tz
208 207 ex φi0..^NtdomFFtztViVi+1FViVi+1tz
209 208 reximdv φi0..^NztdomFFtzztViVi+1FViVi+1tz
210 192 209 mpd φi0..^NztViVi+1FViVi+1tz
211 nfra1 ttViVi+1FViVi+1tz
212 196 eqcomd tViVi+1Ft=FViVi+1t
213 212 fveq2d tViVi+1Ft=FViVi+1t
214 213 adantl tViVi+1FViVi+1tztViVi+1Ft=FViVi+1t
215 rspa tViVi+1FViVi+1tztViVi+1FViVi+1tz
216 214 215 eqbrtrd tViVi+1FViVi+1tztViVi+1Ftz
217 216 ex tViVi+1FViVi+1tztViVi+1Ftz
218 211 217 ralrimi tViVi+1FViVi+1tztViVi+1Ftz
219 218 a1i φi0..^NtViVi+1FViVi+1tztViVi+1Ftz
220 219 reximdv φi0..^NztViVi+1FViVi+1tzztViVi+1Ftz
221 210 220 mpd φi0..^NztViVi+1Ftz
222 nfv iφj0..^M
223 nfcsb1v _ij/iC
224 223 nfel1 ij/iCFQjQj+1limQj
225 222 224 nfim iφj0..^Mj/iCFQjQj+1limQj
226 csbeq1a i=jC=j/iC
227 112 109 oveq12d i=jFQiQi+1limQi=FQjQj+1limQj
228 226 227 eleq12d i=jCFQiQi+1limQij/iCFQjQj+1limQj
229 108 228 imbi12d i=jφi0..^MCFQiQi+1limQiφj0..^Mj/iCFQjQj+1limQj
230 225 229 13 chvarfv φj0..^Mj/iCFQjQj+1limQj
231 230 adantlr φi0..^Nj0..^Mj/iCFQjQj+1limQj
232 93 103 70 104 105 106 117 231 118 124 128 133 fourierdlem96 φi0..^Nifdππifd=ππdcc+πcTTVi=Qysupf0..^M|Qfdππifd=ππdcc+πcTTy<Vij0..^Mj/iCysupf0..^M|Qfdππifd=ππdcc+πcTTy<ViFdππifd=ππdcc+πcTTViFViVi+1limVi
233 nfcsb1v _ij/iU
234 233 nfel1 ij/iUFQjQj+1limQj+1
235 222 234 nfim iφj0..^Mj/iUFQjQj+1limQj+1
236 csbeq1a i=jU=j/iU
237 112 110 oveq12d i=jFQiQi+1limQi+1=FQjQj+1limQj+1
238 236 237 eleq12d i=jUFQiQi+1limQi+1j/iUFQjQj+1limQj+1
239 108 238 imbi12d i=jφi0..^MUFQiQi+1limQi+1φj0..^Mj/iUFQjQj+1limQj+1
240 235 239 14 chvarfv φj0..^Mj/iUFQjQj+1limQj+1
241 240 adantlr φi0..^Nj0..^Mj/iUFQjQj+1limQj+1
242 93 103 70 104 105 106 117 241 157 163 128 133 fourierdlem99 φi0..^Nifee+πeTTVi+1=Qysuph0..^M|Qhgππifg=ππgee+πeTTy<Vi+1j0..^Mj/iUysuph0..^M|Qhgππifg=ππgee+πeTTy<ViFee+πeTTVi+1FViVi+1limVi+1
243 eqeq1 g=sg=0s=0
244 oveq2 g=sX+g=X+s
245 244 fveq2d g=sFX+g=FX+s
246 breq2 g=s0<g0<s
247 246 ifbid g=sif0<gRL=if0<sRL
248 245 247 oveq12d g=sFX+gif0<gRL=FX+sif0<sRL
249 id g=sg=s
250 248 249 oveq12d g=sFX+gif0<gRLg=FX+sif0<sRLs
251 243 250 ifbieq2d g=sifg=00FX+gif0<gRLg=ifs=00FX+sif0<sRLs
252 251 cbvmptv gππifg=00FX+gif0<gRLg=sππifs=00FX+sif0<sRLs
253 eqeq1 o=so=0s=0
254 id o=so=s
255 oveq1 o=so2=s2
256 255 fveq2d o=ssino2=sins2
257 256 oveq2d o=s2sino2=2sins2
258 254 257 oveq12d o=so2sino2=s2sins2
259 253 258 ifbieq2d o=sifo=01o2sino2=ifs=01s2sins2
260 259 cbvmptv oππifo=01o2sino2=sππifs=01s2sins2
261 fveq2 r=sgππifg=00FX+gif0<gRLgr=gππifg=00FX+gif0<gRLgs
262 fveq2 r=soππifo=01o2sino2r=oππifo=01o2sino2s
263 261 262 oveq12d r=sgππifg=00FX+gif0<gRLgroππifo=01o2sino2r=gππifg=00FX+gif0<gRLgsoππifo=01o2sino2s
264 263 cbvmptv rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2r=sππgππifg=00FX+gif0<gRLgsoππifo=01o2sino2s
265 oveq2 d=sk+12d=k+12s
266 265 fveq2d d=ssink+12d=sink+12s
267 266 cbvmptv dππsink+12d=sππsink+12s
268 fveq2 z=srππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rz=rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rs
269 fveq2 z=sdππsink+12dz=dππsink+12ds
270 268 269 oveq12d z=srππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsink+12dz=rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rsdππsink+12ds
271 270 cbvmptv zππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsink+12dz=sππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rsdππsink+12ds
272 fveq2 m=nDm=Dn
273 272 fveq1d m=nDms=Dns
274 273 oveq2d m=nFX+sDms=FX+sDns
275 274 adantr m=nsπ0FX+sDms=FX+sDns
276 275 itgeq2dv m=nπ0FX+sDmsds=π0FX+sDnsds
277 276 cbvmptv mπ0FX+sDmsds=nπ0FX+sDnsds
278 oveq1 c=kc+12=k+12
279 278 oveq1d c=kc+12d=k+12d
280 279 fveq2d c=ksinc+12d=sink+12d
281 280 mpteq2dv c=kdππsinc+12d=dππsink+12d
282 281 fveq1d c=kdππsinc+12dz=dππsink+12dz
283 282 oveq2d c=krππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsinc+12dz=rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsink+12dz
284 283 mpteq2dv c=kzππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsinc+12dz=zππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsink+12dz
285 284 fveq1d c=kzππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsinc+12dzs=zππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsink+12dzs
286 285 adantr c=ksπ0zππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsinc+12dzs=zππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsink+12dzs
287 286 itgeq2dv c=kπ0zππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsinc+12dzsds=π0zππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsink+12dzsds
288 287 oveq1d c=kπ0zππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsinc+12dzsdsπ=π0zππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsink+12dzsdsπ
289 288 cbvmptv cπ0zππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsinc+12dzsdsπ=kπ0zππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsink+12dzsdsπ
290 oveq1 y=symod2π=smod2π
291 290 eqeq1d y=symod2π=0smod2π=0
292 oveq2 y=sm+12y=m+12s
293 292 fveq2d y=ssinm+12y=sinm+12s
294 oveq1 y=sy2=s2
295 294 fveq2d y=ssiny2=sins2
296 295 oveq2d y=s2πsiny2=2πsins2
297 293 296 oveq12d y=ssinm+12y2πsiny2=sinm+12s2πsins2
298 291 297 ifbieq2d y=sifymod2π=02m+12πsinm+12y2πsiny2=ifsmod2π=02m+12πsinm+12s2πsins2
299 298 cbvmptv yifymod2π=02m+12πsinm+12y2πsiny2=sifsmod2π=02m+12πsinm+12s2πsins2
300 simpl m=ksm=k
301 300 oveq2d m=ks2m=2k
302 301 oveq1d m=ks2m+1=2k+1
303 302 oveq1d m=ks2m+12π=2k+12π
304 300 oveq1d m=ksm+12=k+12
305 304 oveq1d m=ksm+12s=k+12s
306 305 fveq2d m=kssinm+12s=sink+12s
307 306 oveq1d m=kssinm+12s2πsins2=sink+12s2πsins2
308 303 307 ifeq12d m=ksifsmod2π=02m+12πsinm+12s2πsins2=ifsmod2π=02k+12πsink+12s2πsins2
309 308 mpteq2dva m=ksifsmod2π=02m+12πsinm+12s2πsins2=sifsmod2π=02k+12πsink+12s2πsins2
310 299 309 eqtrid m=kyifymod2π=02m+12πsinm+12y2πsiny2=sifsmod2π=02k+12πsink+12s2πsins2
311 310 cbvmptv myifymod2π=02m+12πsinm+12y2πsiny2=ksifsmod2π=02k+12πsink+12s2πsins2
312 2 311 eqtri D=ksifsmod2π=02k+12πsink+12s2πsins2
313 eqid rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rπl=rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rπl
314 eqid πlranj0NVjXπl=πlranj0NVjXπl
315 eqid πlranj0NVjXπl1=πlranj0NVjXπl1
316 isoeq1 u=wuIsom<,<0πlranj0NVjXπl1πlranj0NVjXπlwIsom<,<0πlranj0NVjXπl1πlranj0NVjXπl
317 316 cbviotavw ιu|uIsom<,<0πlranj0NVjXπl1πlranj0NVjXπl=ιw|wIsom<,<0πlranj0NVjXπl1πlranj0NVjXπl
318 fveq2 j=iVj=Vi
319 318 oveq1d j=iVjX=ViX
320 319 cbvmptv j0NVjX=i0NViX
321 eqid ιm0..^N|ιu|uIsom<,<0πlranj0NVjXπl1πlranj0NVjXπlbιu|uIsom<,<0πlranj0NVjXπl1πlranj0NVjXπlb+1j0NVjXmj0NVjXm+1=ιm0..^N|ιu|uIsom<,<0πlranj0NVjXπl1πlranj0NVjXπlbιu|uIsom<,<0πlranj0NVjXπl1πlranj0NVjXπlb+1j0NVjXmj0NVjXm+1
322 fveq2 a=srππgππifg=00FX+gif0<gRLgroππifo=01o2sino2ra=rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rs
323 oveq2 a=sb+12a=b+12s
324 323 fveq2d a=ssinb+12a=sinb+12s
325 322 324 oveq12d a=srππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12a=rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12s
326 325 cbvitgv l0rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada=l0rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds
327 326 fveq2i l0rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada=l0rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds
328 327 breq1i l0rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada<i2l0rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds<i2
329 328 anbi2i φi+lπ0bl0rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada<i2φi+lπ0bl0rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds<i2
330 325 cbvitgv πlrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada=πlrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds
331 330 fveq2i πlrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada=πlrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds
332 331 breq1i πlrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada<i2πlrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds<i2
333 329 332 anbi12i φi+lπ0bl0rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada<i2πlrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada<i2φi+lπ0bl0rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds<i2πlrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds<i2
334 1 26 66 91 92 9 134 143 191 221 232 242 252 260 264 267 271 277 289 19 18 16 17 312 313 314 315 317 320 321 333 fourierdlem103 φmπ0FX+sDmsdsL2
335 nnex V
336 335 mptex mA02+n=1mAncosnX+BnsinnXV
337 22 336 eqeltri ZV
338 337 a1i φZV
339 274 adantr m=ns0πFX+sDms=FX+sDns
340 339 itgeq2dv m=n0πFX+sDmsds=0πFX+sDnsds
341 340 cbvmptv m0πFX+sDmsds=n0πFX+sDnsds
342 285 adantr c=ks0πzππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsinc+12dzs=zππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsink+12dzs
343 342 itgeq2dv c=k0πzππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsinc+12dzsds=0πzππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsink+12dzsds
344 343 oveq1d c=k0πzππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsinc+12dzsdsπ=0πzππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsink+12dzsdsπ
345 344 cbvmptv c0πzππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsinc+12dzsdsπ=k0πzππrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rzdππsink+12dzsdsπ
346 eqid rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2reπ=rππgππifg=00FX+gif0<gRLgroππifo=01o2sino2reπ
347 eqid eπranj0NVjXeπ=eπranj0NVjXeπ
348 eqid eπranj0NVjXeπ1=eπranj0NVjXeπ1
349 isoeq1 u=vuIsom<,<0eπranj0NVjXeπ1eπranj0NVjXeπvIsom<,<0eπranj0NVjXeπ1eπranj0NVjXeπ
350 349 cbviotavw ιu|uIsom<,<0eπranj0NVjXeπ1eπranj0NVjXeπ=ιv|vIsom<,<0eπranj0NVjXeπ1eπranj0NVjXeπ
351 eqid ιa0..^N|ιu|uIsom<,<0eπranj0NVjXeπ1eπranj0NVjXeπbιu|uIsom<,<0eπranj0NVjXeπ1eπranj0NVjXeπb+1j0NVjXaj0NVjXa+1=ιa0..^N|ιu|uIsom<,<0eπranj0NVjXeπ1eπranj0NVjXeπbιu|uIsom<,<0eπranj0NVjXeπ1eπranj0NVjXeπb+1j0NVjXaj0NVjXa+1
352 325 cbvitgv 0erππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada=0erππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds
353 352 fveq2i 0erππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada=0erππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds
354 353 breq1i 0erππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada<q20erππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds<q2
355 354 anbi2i φq+e0πb0erππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada<q2φq+e0πb0erππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds<q2
356 325 cbvitgv eπrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada=eπrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds
357 356 fveq2i eπrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada=eπrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds
358 357 breq1i eπrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada<q2eπrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds<q2
359 355 358 anbi12i φq+e0πb0erππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada<q2eπrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rasinb+12ada<q2φq+e0πb0erππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds<q2eπrππgππifg=00FX+gif0<gRLgroππifo=01o2sino2rssinb+12sds<q2
360 1 26 66 91 92 9 134 143 191 221 232 242 252 260 264 267 271 341 345 19 18 16 17 312 346 347 348 350 320 351 359 fourierdlem104 φm0πFX+sDmsdsR2
361 eqidd φnmπ0FX+sDmsds=mπ0FX+sDmsds
362 276 adantl φnm=nπ0FX+sDmsds=π0FX+sDnsds
363 simpr φnn
364 elioore sπ0s
365 1 adantr φsF:
366 26 adantr φsX
367 simpr φss
368 366 367 readdcld φsX+s
369 365 368 ffvelcdmd φsFX+s
370 369 adantlr φnsFX+s
371 2 dirkerre nsDns
372 371 adantll φnsDns
373 370 372 remulcld φnsFX+sDns
374 364 373 sylan2 φnsπ0FX+sDns
375 ioossicc π0π0
376 78 leidi ππ
377 79 71 77 ltleii 0π
378 iccss ππππ0ππ0ππ
379 78 71 376 377 378 mp4an π0ππ
380 375 379 sstri π0ππ
381 380 a1i φnπ0ππ
382 ioombl π0domvol
383 382 a1i φnπ0domvol
384 1 adantr φsππF:
385 26 adantr φsππX
386 73 72 iccssred φππ
387 386 sselda φsππs
388 385 387 readdcld φsππX+s
389 384 388 ffvelcdmd φsππFX+s
390 389 adantlr φnsππFX+s
391 iccssre ππππ
392 78 71 391 mp2an ππ
393 392 sseli sππs
394 393 371 sylan2 nsππDns
395 394 adantll φnsππDns
396 390 395 remulcld φnsππFX+sDns
397 78 a1i φnπ
398 71 a1i φnπ
399 1 adantr φnF:
400 26 adantr φnX
401 91 adantr φnN
402 92 adantr φnVnp0n|p0=-π+Xpn=π+Xi0..^npi<pi+1N
403 134 adantlr φni0..^NFViVi+1:ViVi+1cn
404 232 adantlr φni0..^Nifdππifd=ππdcc+πcTTVi=Qysupf0..^M|Qfdππifd=ππdcc+πcTTy<Vij0..^Mj/iCysupf0..^M|Qfdππifd=ππdcc+πcTTy<ViFdππifd=ππdcc+πcTTViFViVi+1limVi
405 242 adantlr φni0..^Nifee+πeTTVi+1=Qysuph0..^M|Qhgππifg=ππgee+πeTTy<Vi+1j0..^Mj/iUysuph0..^M|Qhgππifg=ππgee+πeTTy<ViFee+πeTTVi+1FViVi+1limVi+1
406 2 dirkercncf nDn:cn
407 406 adantl φnDn:cn
408 eqid sππFX+sDns=sππFX+sDns
409 397 398 399 400 66 401 402 403 404 405 320 3 407 408 fourierdlem84 φnsππFX+sDns𝐿1
410 381 383 396 409 iblss φnsπ0FX+sDns𝐿1
411 374 410 itgcl φnπ0FX+sDnsds
412 361 362 363 411 fvmptd φnmπ0FX+sDmsdsn=π0FX+sDnsds
413 412 411 eqeltrd φnmπ0FX+sDmsdsn
414 eqidd φnm0πFX+sDmsds=m0πFX+sDmsds
415 340 adantl φnm=n0πFX+sDmsds=0πFX+sDnsds
416 1 adantr φs0πF:
417 26 adantr φs0πX
418 elioore s0πs
419 418 adantl φs0πs
420 417 419 readdcld φs0πX+s
421 416 420 ffvelcdmd φs0πFX+s
422 421 adantlr φns0πFX+s
423 418 371 sylan2 ns0πDns
424 423 adantll φns0πDns
425 422 424 remulcld φns0πFX+sDns
426 ioossicc 0π0π
427 78 79 76 ltleii π0
428 71 leidi ππ
429 iccss πππ0ππ0πππ
430 78 71 427 428 429 mp4an 0πππ
431 426 430 sstri 0πππ
432 431 a1i φn0πππ
433 ioombl 0πdomvol
434 433 a1i φn0πdomvol
435 432 434 396 409 iblss φns0πFX+sDns𝐿1
436 425 435 itgcl φn0πFX+sDnsds
437 414 415 363 436 fvmptd φnm0πFX+sDmsdsn=0πFX+sDnsds
438 437 436 eqeltrd φnm0πFX+sDmsdsn
439 eleq1w m=nmn
440 439 anbi2d m=nφmφn
441 fveq2 m=nZm=Zn
442 276 340 oveq12d m=nπ0FX+sDmsds+0πFX+sDmsds=π0FX+sDnsds+0πFX+sDnsds
443 441 442 eqeq12d m=nZm=π0FX+sDmsds+0πFX+sDmsdsZn=π0FX+sDnsds+0πFX+sDnsds
444 440 443 imbi12d m=nφmZm=π0FX+sDmsds+0πFX+sDmsdsφnZn=π0FX+sDnsds+0πFX+sDnsds
445 oveq1 n=mnx=mx
446 445 fveq2d n=mcosnx=cosmx
447 446 oveq2d n=mFxcosnx=Fxcosmx
448 447 adantr n=mxππFxcosnx=Fxcosmx
449 448 itgeq2dv n=mππFxcosnxdx=ππFxcosmxdx
450 449 oveq1d n=mππFxcosnxdxπ=ππFxcosmxdxπ
451 450 cbvmptv n0ππFxcosnxdxπ=m0ππFxcosmxdxπ
452 20 451 eqtri A=m0ππFxcosmxdxπ
453 445 fveq2d n=msinnx=sinmx
454 453 oveq2d n=mFxsinnx=Fxsinmx
455 454 adantr n=mxππFxsinnx=Fxsinmx
456 455 itgeq2dv n=mππFxsinnxdx=ππFxsinmxdx
457 456 oveq1d n=mππFxsinnxdxπ=ππFxsinmxdxπ
458 457 cbvmptv nππFxsinnxdxπ=mππFxsinmxdxπ
459 21 458 eqtri B=mππFxsinmxdxπ
460 fveq2 n=kAn=Ak
461 oveq1 n=knX=kX
462 461 fveq2d n=kcosnX=coskX
463 460 462 oveq12d n=kAncosnX=AkcoskX
464 fveq2 n=kBn=Bk
465 461 fveq2d n=ksinnX=sinkX
466 464 465 oveq12d n=kBnsinnX=BksinkX
467 463 466 oveq12d n=kAncosnX+BnsinnX=AkcoskX+BksinkX
468 467 cbvsumv n=1mAncosnX+BnsinnX=k=1mAkcoskX+BksinkX
469 468 oveq2i A02+n=1mAncosnX+BnsinnX=A02+k=1mAkcoskX+BksinkX
470 469 mpteq2i mA02+n=1mAncosnX+BnsinnX=mA02+k=1mAkcoskX+BksinkX
471 oveq2 m=n1m=1n
472 471 sumeq1d m=nk=1mAkcoskX+BksinkX=k=1nAkcoskX+BksinkX
473 472 oveq2d m=nA02+k=1mAkcoskX+BksinkX=A02+k=1nAkcoskX+BksinkX
474 473 cbvmptv mA02+k=1mAkcoskX+BksinkX=nA02+k=1nAkcoskX+BksinkX
475 fveq2 k=mAk=Am
476 oveq1 k=mkX=mX
477 476 fveq2d k=mcoskX=cosmX
478 475 477 oveq12d k=mAkcoskX=AmcosmX
479 fveq2 k=mBk=Bm
480 476 fveq2d k=msinkX=sinmX
481 479 480 oveq12d k=mBksinkX=BmsinmX
482 478 481 oveq12d k=mAkcoskX+BksinkX=AmcosmX+BmsinmX
483 482 cbvsumv k=1nAkcoskX+BksinkX=m=1nAmcosmX+BmsinmX
484 483 oveq2i A02+k=1nAkcoskX+BksinkX=A02+m=1nAmcosmX+BmsinmX
485 484 mpteq2i nA02+k=1nAkcoskX+BksinkX=nA02+m=1nAmcosmX+BmsinmX
486 474 485 eqtri mA02+k=1mAkcoskX+BksinkX=nA02+m=1nAmcosmX+BmsinmX
487 22 470 486 3eqtri Z=nA02+m=1nAmcosmX+BmsinmX
488 oveq2 y=xX+y=X+x
489 488 fveq2d y=xFX+y=FX+x
490 fveq2 y=xDmy=Dmx
491 489 490 oveq12d y=xFX+yDmy=FX+xDmx
492 491 cbvmptv yFX+yDmy=xFX+xDmx
493 eqid np0n|p0=-π-Xpn=πXi0..^npi<pi+1=np0n|p0=-π-Xpn=πXi0..^npi<pi+1
494 fveq2 j=iQj=Qi
495 494 oveq1d j=iQjX=QiX
496 495 cbvmptv j0MQjX=i0MQiX
497 452 459 487 2 3 4 5 8 1 11 492 12 13 14 10 493 496 fourierdlem111 φmZm=π0FX+sDmsds+0πFX+sDmsds
498 444 497 chvarvv φnZn=π0FX+sDnsds+0πFX+sDnsds
499 412 437 oveq12d φnmπ0FX+sDmsdsn+m0πFX+sDmsdsn=π0FX+sDnsds+0πFX+sDnsds
500 498 499 eqtr4d φnZn=mπ0FX+sDmsdsn+m0πFX+sDmsdsn
501 41 49 52 65 39 40 334 338 360 413 438 500 climaddf φZL2+R2
502 limccl F−∞XlimX
503 502 18 sselid φL
504 limccl FX+∞limX
505 504 19 sselid φR
506 2cnd φ2
507 2pos 0<2
508 507 a1i φ0<2
509 508 gt0ne0d φ20
510 503 505 506 509 divdird φL+R2=L2+R2
511 501 510 breqtrrd φZL+R2
512 0nn0 00
513 1 adantr φ00F:
514 eqid ππ=ππ
515 ioossre ππ
516 515 a1i φππ
517 1 516 feqresmpt φFππ=xππFx
518 ioossicc ππππ
519 518 a1i φππππ
520 ioombl ππdomvol
521 520 a1i φππdomvol
522 1 adantr φxππF:
523 386 sselda φxππx
524 522 523 ffvelcdmd φxππFx
525 1 386 feqresmpt φFππ=xππFx
526 187 a1i φ
527 1 526 fssd φF:
528 527 386 fssresd φFππ:ππ
529 ioossicc QiQi+1QiQi+1
530 78 rexri π*
531 530 a1i φi0..^Mπ*
532 71 rexri π*
533 532 a1i φi0..^Mπ*
534 3 4 5 fourierdlem15 φQ:0Mππ
535 534 adantr φi0..^MQ:0Mππ
536 simpr φi0..^Mi0..^M
537 531 533 535 536 fourierdlem8 φi0..^MQiQi+1ππ
538 529 537 sstrid φi0..^MQiQi+1ππ
539 538 resabs1d φi0..^MFππQiQi+1=FQiQi+1
540 539 12 eqeltrd φi0..^MFππQiQi+1:QiQi+1cn
541 539 eqcomd φi0..^MFQiQi+1=FππQiQi+1
542 541 oveq1d φi0..^MFQiQi+1limQi=FππQiQi+1limQi
543 13 542 eleqtrd φi0..^MCFππQiQi+1limQi
544 541 oveq1d φi0..^MFQiQi+1limQi+1=FππQiQi+1limQi+1
545 14 544 eleqtrd φi0..^MUFππQiQi+1limQi+1
546 3 4 5 528 540 543 545 fourierdlem69 φFππ𝐿1
547 525 546 eqeltrrd φxππFx𝐿1
548 519 521 524 547 iblss φxππFx𝐿1
549 517 548 eqeltrd φFππ𝐿1
550 549 adantr φ00Fππ𝐿1
551 simpr φ0000
552 513 514 550 20 551 fourierdlem16 φ00A0xππFx𝐿1ππFxcos0xdx
553 552 simplld φ00A0
554 512 553 mpan2 φA0
555 554 rehalfcld φA02
556 555 recnd φA02
557 335 mptex nk=1nAkcoskX+BksinkXV
558 557 a1i φnk=1nAkcoskX+BksinkXV
559 simpr φmm
560 555 adantr φmA02
561 fzfid φm1mFin
562 simpll φmn1mφ
563 elfznn n1mn
564 563 adantl φmn1mn
565 simpl φnφ
566 363 nnnn0d φnn0
567 eleq1w k=nk0n0
568 567 anbi2d k=nφk0φn0
569 fveq2 k=nAk=An
570 569 eleq1d k=nAkAn
571 568 570 imbi12d k=nφk0Akφn0An
572 1 adantr φk0F:
573 549 adantr φk0Fππ𝐿1
574 simpr φk0k0
575 572 514 573 20 574 fourierdlem16 φk0AkxππFx𝐿1ππFxcoskxdx
576 575 simplld φk0Ak
577 571 576 chvarvv φn0An
578 565 566 577 syl2anc φnAn
579 363 nnred φnn
580 579 400 remulcld φnnX
581 580 recoscld φncosnX
582 578 581 remulcld φnAncosnX
583 eleq1w k=nkn
584 583 anbi2d k=nφkφn
585 fveq2 k=nBk=Bn
586 585 eleq1d k=nBkBn
587 584 586 imbi12d k=nφkBkφnBn
588 1 adantr φkF:
589 549 adantr φkFππ𝐿1
590 simpr φkk
591 588 514 589 21 590 fourierdlem21 φkBkxππFxsinkx𝐿1ππFxsinkxdx
592 591 simplld φkBk
593 587 592 chvarvv φnBn
594 580 resincld φnsinnX
595 593 594 remulcld φnBnsinnX
596 582 595 readdcld φnAncosnX+BnsinnX
597 562 564 596 syl2anc φmn1mAncosnX+BnsinnX
598 561 597 fsumrecl φmn=1mAncosnX+BnsinnX
599 560 598 readdcld φmA02+n=1mAncosnX+BnsinnX
600 22 fvmpt2 mA02+n=1mAncosnX+BnsinnXZm=A02+n=1mAncosnX+BnsinnX
601 559 599 600 syl2anc φmZm=A02+n=1mAncosnX+BnsinnX
602 601 599 eqeltrd φmZm
603 602 recnd φmZm
604 eqidd φmnk=1nAkcoskX+BksinkX=nk=1nAkcoskX+BksinkX
605 oveq2 n=m1n=1m
606 605 sumeq1d n=mk=1nAkcoskX+BksinkX=k=1mAkcoskX+BksinkX
607 606 adantl φmn=mk=1nAkcoskX+BksinkX=k=1mAkcoskX+BksinkX
608 sumex k=1mAkcoskX+BksinkXV
609 608 a1i φmk=1mAkcoskX+BksinkXV
610 604 607 559 609 fvmptd φmnk=1nAkcoskX+BksinkXm=k=1mAkcoskX+BksinkX
611 560 recnd φmA02
612 598 recnd φmn=1mAncosnX+BnsinnX
613 611 612 pncan2d φmA02+n=1mAncosnX+BnsinnX-A02=n=1mAncosnX+BnsinnX
614 613 468 eqtr2di φmk=1mAkcoskX+BksinkX=A02+n=1mAncosnX+BnsinnX-A02
615 ovex A02+n=1mAncosnX+BnsinnXV
616 22 fvmpt2 mA02+n=1mAncosnX+BnsinnXVZm=A02+n=1mAncosnX+BnsinnX
617 559 615 616 sylancl φmZm=A02+n=1mAncosnX+BnsinnX
618 617 eqcomd φmA02+n=1mAncosnX+BnsinnX=Zm
619 618 oveq1d φmA02+n=1mAncosnX+BnsinnX-A02=ZmA02
620 610 614 619 3eqtrd φmnk=1nAkcoskX+BksinkXm=ZmA02
621 39 40 511 556 558 603 620 climsubc1 φnk=1nAkcoskX+BksinkXL+R2A02
622 seqex seq1+jAjcosjX+BjsinjXV
623 622 a1i φseq1+jAjcosjX+BjsinjXV
624 eqidd φlnk=1nAkcoskX+BksinkX=nk=1nAkcoskX+BksinkX
625 oveq2 n=l1n=1l
626 625 sumeq1d n=lk=1nAkcoskX+BksinkX=k=1lAkcoskX+BksinkX
627 626 adantl φln=lk=1nAkcoskX+BksinkX=k=1lAkcoskX+BksinkX
628 simpr φll
629 fzfid φl1lFin
630 elfznn k1lk
631 630 nnnn0d k1lk0
632 631 576 sylan2 φk1lAk
633 630 nnred k1lk
634 633 adantl φk1lk
635 8 adantr φk1lX
636 634 635 remulcld φk1lkX
637 636 recoscld φk1lcoskX
638 632 637 remulcld φk1lAkcoskX
639 630 592 sylan2 φk1lBk
640 636 resincld φk1lsinkX
641 639 640 remulcld φk1lBksinkX
642 638 641 readdcld φk1lAkcoskX+BksinkX
643 642 adantlr φlk1lAkcoskX+BksinkX
644 629 643 fsumrecl φlk=1lAkcoskX+BksinkX
645 624 627 628 644 fvmptd φlnk=1nAkcoskX+BksinkXl=k=1lAkcoskX+BksinkX
646 eleq1w n=lnl
647 646 anbi2d n=lφnφl
648 fveq2 n=lseq1+jAjcosjX+BjsinjXn=seq1+jAjcosjX+BjsinjXl
649 626 648 eqeq12d n=lk=1nAkcoskX+BksinkX=seq1+jAjcosjX+BjsinjXnk=1lAkcoskX+BksinkX=seq1+jAjcosjX+BjsinjXl
650 647 649 imbi12d n=lφnk=1nAkcoskX+BksinkX=seq1+jAjcosjX+BjsinjXnφlk=1lAkcoskX+BksinkX=seq1+jAjcosjX+BjsinjXl
651 eqidd φnk1njAjcosjX+BjsinjX=jAjcosjX+BjsinjX
652 fveq2 j=kAj=Ak
653 oveq1 j=kjX=kX
654 653 fveq2d j=kcosjX=coskX
655 652 654 oveq12d j=kAjcosjX=AkcoskX
656 fveq2 j=kBj=Bk
657 653 fveq2d j=ksinjX=sinkX
658 656 657 oveq12d j=kBjsinjX=BksinkX
659 655 658 oveq12d j=kAjcosjX+BjsinjX=AkcoskX+BksinkX
660 659 adantl φnk1nj=kAjcosjX+BjsinjX=AkcoskX+BksinkX
661 elfznn k1nk
662 661 adantl φnk1nk
663 simpll φnk1nφ
664 nnnn0 kk0
665 nn0re k0k
666 665 adantl φk0k
667 8 adantr φk0X
668 666 667 remulcld φk0kX
669 668 recoscld φk0coskX
670 576 669 remulcld φk0AkcoskX
671 664 670 sylan2 φkAkcoskX
672 664 668 sylan2 φkkX
673 672 resincld φksinkX
674 592 673 remulcld φkBksinkX
675 671 674 readdcld φkAkcoskX+BksinkX
676 663 662 675 syl2anc φnk1nAkcoskX+BksinkX
677 651 660 662 676 fvmptd φnk1njAjcosjX+BjsinjXk=AkcoskX+BksinkX
678 363 39 eleqtrdi φnn1
679 676 recnd φnk1nAkcoskX+BksinkX
680 677 678 679 fsumser φnk=1nAkcoskX+BksinkX=seq1+jAjcosjX+BjsinjXn
681 650 680 chvarvv φlk=1lAkcoskX+BksinkX=seq1+jAjcosjX+BjsinjXl
682 645 681 eqtrd φlnk=1nAkcoskX+BksinkXl=seq1+jAjcosjX+BjsinjXl
683 39 558 623 40 682 climeq φnk=1nAkcoskX+BksinkXL+R2A02seq1+jAjcosjX+BjsinjXL+R2A02
684 621 683 mpbid φseq1+jAjcosjX+BjsinjXL+R2A02
685 38 684 eqbrtrd φseq1+SL+R2A02
686 eqidd φnjAjcosjX+BjsinjX=jAjcosjX+BjsinjX
687 fveq2 j=nAj=An
688 oveq1 j=njX=nX
689 688 fveq2d j=ncosjX=cosnX
690 687 689 oveq12d j=nAjcosjX=AncosnX
691 fveq2 j=nBj=Bn
692 688 fveq2d j=nsinjX=sinnX
693 691 692 oveq12d j=nBjsinjX=BnsinnX
694 690 693 oveq12d j=nAjcosjX+BjsinjX=AncosnX+BnsinnX
695 694 adantl φnj=nAjcosjX+BjsinjX=AncosnX+BnsinnX
696 686 695 363 596 fvmptd φnjAjcosjX+BjsinjXn=AncosnX+BnsinnX
697 596 recnd φnAncosnX+BnsinnX
698 39 40 696 697 684 isumclim φnAncosnX+BnsinnX=L+R2A02
699 698 oveq2d φA02+nAncosnX+BnsinnX=A02+L+R2-A02
700 503 505 addcld φL+R
701 700 halfcld φL+R2
702 556 701 pncan3d φA02+L+R2-A02=L+R2
703 699 702 eqtrd φA02+nAncosnX+BnsinnX=L+R2
704 685 703 jca φseq1+SL+R2A02A02+nAncosnX+BnsinnX=L+R2