Metamath Proof Explorer


Theorem fourierdlem94

Description: For a piecewise smooth function, the left and the right limits exist at any point. (Contributed by Glauco Siliprandi, 11-Dec-2019)

Ref Expression
Hypotheses fourierdlem94.f φF:
fourierdlem94.t T=2π
fourierdlem94.per φxFx+T=Fx
fourierdlem94.x φX
fourierdlem94.p P=np0n|p0=πpn=πi0..^npi<pi+1
fourierdlem94.m φM
fourierdlem94.q φQPM
fourierdlem94.dvcn φi0..^MFQiQi+1:QiQi+1cn
fourierdlem94.dvlb φi0..^MFQiQi+1limQi
fourierdlem94.dvub φi0..^MFQiQi+1limQi+1
Assertion fourierdlem94 φF−∞XlimXFX+∞limX

Proof

Step Hyp Ref Expression
1 fourierdlem94.f φF:
2 fourierdlem94.t T=2π
3 fourierdlem94.per φxFx+T=Fx
4 fourierdlem94.x φX
5 fourierdlem94.p P=np0n|p0=πpn=πi0..^npi<pi+1
6 fourierdlem94.m φM
7 fourierdlem94.q φQPM
8 fourierdlem94.dvcn φi0..^MFQiQi+1:QiQi+1cn
9 fourierdlem94.dvlb φi0..^MFQiQi+1limQi
10 fourierdlem94.dvub φi0..^MFQiQi+1limQi+1
11 pire π
12 11 renegcli π
13 12 a1i φπ
14 11 a1i φπ
15 negpilt0 π<0
16 pipos 0<π
17 0re 0
18 12 17 11 lttri π<00<ππ<π
19 15 16 18 mp2an π<π
20 19 a1i φπ<π
21 picn π
22 21 2timesi 2π=π+π
23 21 21 subnegi ππ=π+π
24 22 2 23 3eqtr4i T=ππ
25 ssid
26 25 a1i φ
27 simp2 φxkx
28 zre kk
29 28 3ad2ant3 φxkk
30 2re 2
31 30 11 remulcli 2π
32 31 a1i φ2π
33 2 32 eqeltrid φT
34 33 adantr φkT
35 34 3adant2 φxkT
36 29 35 remulcld φxkkT
37 27 36 readdcld φxkx+kT
38 simp1 φxkφ
39 simp3 φxkk
40 ax-resscn
41 40 a1i φ
42 1 41 fssd φF:
43 42 adantr φkF:
44 43 adantr φkxF:
45 34 adantr φkxT
46 simplr φkxk
47 simpr φkxx
48 eleq1w x=yxy
49 48 anbi2d x=yφxφy
50 oveq1 x=yx+T=y+T
51 50 fveq2d x=yFx+T=Fy+T
52 fveq2 x=yFx=Fy
53 51 52 eqeq12d x=yFx+T=FxFy+T=Fy
54 49 53 imbi12d x=yφxFx+T=FxφyFy+T=Fy
55 54 3 chvarvv φyFy+T=Fy
56 55 ad4ant14 φkxyFy+T=Fy
57 44 45 46 47 56 fperiodmul φkxFx+kT=Fx
58 38 39 27 57 syl21anc φxkFx+kT=Fx
59 40 a1i φi0..^M
60 ioossre QiQi+1
61 60 a1i φQiQi+1
62 1 61 fssresd φFQiQi+1:QiQi+1
63 62 41 fssd φFQiQi+1:QiQi+1
64 63 adantr φi0..^MFQiQi+1:QiQi+1
65 60 a1i φi0..^MQiQi+1
66 42 adantr φi0..^MF:
67 25 a1i φi0..^M
68 eqid TopOpenfld=TopOpenfld
69 68 tgioo2 topGenran.=TopOpenfld𝑡
70 68 69 dvres F:QiQi+1DFQiQi+1=FinttopGenran.QiQi+1
71 59 66 67 65 70 syl22anc φi0..^MDFQiQi+1=FinttopGenran.QiQi+1
72 71 dmeqd φi0..^MdomFQiQi+1=domFinttopGenran.QiQi+1
73 ioontr inttopGenran.QiQi+1=QiQi+1
74 73 reseq2i FinttopGenran.QiQi+1=FQiQi+1
75 74 dmeqi domFinttopGenran.QiQi+1=domFQiQi+1
76 75 a1i φi0..^MdomFinttopGenran.QiQi+1=domFQiQi+1
77 cncff FQiQi+1:QiQi+1cnFQiQi+1:QiQi+1
78 fdm FQiQi+1:QiQi+1domFQiQi+1=QiQi+1
79 8 77 78 3syl φi0..^MdomFQiQi+1=QiQi+1
80 72 76 79 3eqtrd φi0..^MdomFQiQi+1=QiQi+1
81 dvcn FQiQi+1:QiQi+1QiQi+1domFQiQi+1=QiQi+1FQiQi+1:QiQi+1cn
82 59 64 65 80 81 syl31anc φi0..^MFQiQi+1:QiQi+1cn
83 65 40 sstrdi φi0..^MQiQi+1
84 5 fourierdlem2 MQPMQ0MQ0=πQM=πi0..^MQi<Qi+1
85 6 84 syl φQPMQ0MQ0=πQM=πi0..^MQi<Qi+1
86 7 85 mpbid φQ0MQ0=πQM=πi0..^MQi<Qi+1
87 86 simpld φQ0M
88 elmapi Q0MQ:0M
89 87 88 syl φQ:0M
90 89 adantr φi0..^MQ:0M
91 elfzofz i0..^Mi0M
92 91 adantl φi0..^Mi0M
93 90 92 ffvelcdmd φi0..^MQi
94 93 rexrd φi0..^MQi*
95 fzofzp1 i0..^Mi+10M
96 95 adantl φi0..^Mi+10M
97 90 96 ffvelcdmd φi0..^MQi+1
98 86 simprrd φi0..^MQi<Qi+1
99 98 r19.21bi φi0..^MQi<Qi+1
100 68 94 97 99 lptioo2cn φi0..^MQi+1limPtTopOpenfldQiQi+1
101 62 adantr φi0..^MFQiQi+1:QiQi+1
102 41 42 26 dvbss φdomF
103 dvfre F:F:domF
104 1 26 103 syl2anc φF:domF
105 86 simprd φQ0=πQM=πi0..^MQi<Qi+1
106 105 simplld φQ0=π
107 105 simplrd φQM=π
108 8 77 syl φi0..^MFQiQi+1:QiQi+1
109 97 rexrd φi0..^MQi+1*
110 68 109 93 99 lptioo1cn φi0..^MQilimPtTopOpenfldQiQi+1
111 108 83 110 9 68 ellimciota φi0..^Mιx|xFQiQi+1limQiFQiQi+1limQi
112 108 83 100 10 68 ellimciota φi0..^Mιx|xFQiQi+1limQi+1FQiQi+1limQi+1
113 28 adantl φkk
114 113 34 remulcld φkkT
115 43 adantr φktF:
116 34 adantr φktT
117 simplr φktk
118 simpr φktt
119 3 ad4ant14 φktxFx+T=Fx
120 115 116 117 118 119 fperiodmul φktFt+kT=Ft
121 eqid DF=DF
122 43 114 120 121 fperdvper φktdomFt+kTdomFFt+kT=Ft
123 122 an32s φtdomFkt+kTdomFFt+kT=Ft
124 123 simpld φtdomFkt+kTdomF
125 123 simprd φtdomFkFt+kT=Ft
126 fveq2 j=iQj=Qi
127 oveq1 j=ij+1=i+1
128 127 fveq2d j=iQj+1=Qi+1
129 126 128 oveq12d j=iQjQj+1=QiQi+1
130 129 cbvmptv j0..^MQjQj+1=i0..^MQiQi+1
131 eqid tt+πtTT=tt+πtTT
132 102 104 13 14 20 24 6 89 106 107 8 111 112 124 125 130 131 fourierdlem71 φztdomFFtz
133 132 adantr φi0..^MztdomFFtz
134 nfv tφi0..^M
135 nfra1 ttdomFFtz
136 134 135 nfan tφi0..^MtdomFFtz
137 71 74 eqtrdi φi0..^MDFQiQi+1=FQiQi+1
138 137 fveq1d φi0..^MFQiQi+1t=FQiQi+1t
139 fvres tQiQi+1FQiQi+1t=Ft
140 138 139 sylan9eq φi0..^MtQiQi+1FQiQi+1t=Ft
141 140 fveq2d φi0..^MtQiQi+1FQiQi+1t=Ft
142 141 adantlr φi0..^MtdomFFtztQiQi+1FQiQi+1t=Ft
143 simplr φi0..^MtdomFFtztQiQi+1tdomFFtz
144 ssdmres QiQi+1domFdomFQiQi+1=QiQi+1
145 79 144 sylibr φi0..^MQiQi+1domF
146 145 ad2antrr φi0..^MtdomFFtztQiQi+1QiQi+1domF
147 simpr φi0..^MtdomFFtztQiQi+1tQiQi+1
148 146 147 sseldd φi0..^MtdomFFtztQiQi+1tdomF
149 rspa tdomFFtztdomFFtz
150 143 148 149 syl2anc φi0..^MtdomFFtztQiQi+1Ftz
151 142 150 eqbrtrd φi0..^MtdomFFtztQiQi+1FQiQi+1tz
152 151 ex φi0..^MtdomFFtztQiQi+1FQiQi+1tz
153 136 152 ralrimi φi0..^MtdomFFtztQiQi+1FQiQi+1tz
154 153 ex φi0..^MtdomFFtztQiQi+1FQiQi+1tz
155 154 reximdv φi0..^MztdomFFtzztQiQi+1FQiQi+1tz
156 133 155 mpd φi0..^MztQiQi+1FQiQi+1tz
157 93 97 101 80 156 ioodvbdlimc2 φi0..^MFQiQi+1limQi+1
158 64 83 100 157 68 ellimciota φi0..^Mιy|yFQiQi+1limQi+1FQiQi+1limQi+1
159 oveq2 y=xπy=πx
160 159 oveq1d y=xπyT=πxT
161 160 fveq2d y=xπyT=πxT
162 161 oveq1d y=xπyTT=πxTT
163 162 cbvmptv yπyTT=xπxTT
164 id z=xz=x
165 fveq2 z=xyπyTTz=yπyTTx
166 164 165 oveq12d z=xz+yπyTTz=x+yπyTTx
167 166 cbvmptv zz+yπyTTz=xx+yπyTTx
168 13 14 20 5 24 6 7 26 1 37 58 82 158 4 163 167 fourierdlem49 φF−∞XlimX
169 93 97 101 80 156 ioodvbdlimc1 φi0..^MFQiQi+1limQi
170 64 83 110 169 68 ellimciota φi0..^Mιy|yFQiQi+1limQiFQiQi+1limQi
171 biid φi0..^MwQiQi+1kw=X+kTφi0..^MwQiQi+1kw=X+kT
172 13 14 20 5 24 6 7 1 37 58 82 170 4 163 167 171 fourierdlem48 φFX+∞limX
173 168 172 jca φF−∞XlimXFX+∞limX