Metamath Proof Explorer


Theorem xrlimcnp

Description: Relate a limit of a real-valued sequence at infinity to the continuity of the corresponding extended real function at +oo . Since any ~>r limit can be written in the form on the left side of the implication, this shows that real limits are a special case of topological continuity at a point. (Contributed by Mario Carneiro, 8-Sep-2015)

Ref Expression
Hypotheses xrlimcnp.a φ A = B +∞
xrlimcnp.b φ B
xrlimcnp.r φ x A R
xrlimcnp.c x = +∞ R = C
xrlimcnp.j J = TopOpen fld
xrlimcnp.k K = ordTop 𝑡 A
Assertion xrlimcnp φ x B R C x A R K CnP J +∞

Proof

Step Hyp Ref Expression
1 xrlimcnp.a φ A = B +∞
2 xrlimcnp.b φ B
3 xrlimcnp.r φ x A R
4 xrlimcnp.c x = +∞ R = C
5 xrlimcnp.j J = TopOpen fld
6 xrlimcnp.k K = ordTop 𝑡 A
7 3 fmpttd φ x A R : A
8 7 adantr φ x B R C x A R : A
9 eqid x A R = x A R
10 ssun2 +∞ B +∞
11 pnfex +∞ V
12 11 snid +∞ +∞
13 10 12 sselii +∞ B +∞
14 13 1 eleqtrrid φ +∞ A
15 4 eleq1d x = +∞ R C
16 3 ralrimiva φ x A R
17 15 16 14 rspcdva φ C
18 9 4 14 17 fvmptd3 φ x A R +∞ = C
19 18 ad2antrr φ x B R C y J x A R +∞ = C
20 19 eleq1d φ x B R C y J x A R +∞ y C y
21 cnxmet abs ∞Met
22 5 cnfldtopn J = MetOpen abs
23 22 mopni2 abs ∞Met y J C y r + C ball abs r y
24 21 23 mp3an1 y J C y r + C ball abs r y
25 ssun1 B B +∞
26 25 1 sseqtrrid φ B A
27 ssralv B A x A R x B R
28 26 16 27 sylc φ x B R
29 28 ad2antrr φ x B R C r + C ball abs r y x B R
30 simprl φ x B R C r + C ball abs r y r +
31 simplr φ x B R C r + C ball abs r y x B R C
32 29 30 31 rlimi φ x B R C r + C ball abs r y k x B k x R C < r
33 letop ordTop Top
34 ressxr *
35 2 34 sstrdi φ B *
36 pnfxr +∞ *
37 36 a1i φ +∞ *
38 37 snssd φ +∞ *
39 35 38 unssd φ B +∞ *
40 1 39 eqsstrd φ A *
41 xrex * V
42 41 ssex A * A V
43 40 42 syl φ A V
44 43 ad2antrr φ r + C ball abs r y k x B k x R C < r A V
45 iocpnfordt k +∞ ordTop
46 45 a1i φ r + C ball abs r y k x B k x R C < r k +∞ ordTop
47 elrestr ordTop Top A V k +∞ ordTop k +∞ A ordTop 𝑡 A
48 33 44 46 47 mp3an2i φ r + C ball abs r y k x B k x R C < r k +∞ A ordTop 𝑡 A
49 48 6 eleqtrrdi φ r + C ball abs r y k x B k x R C < r k +∞ A K
50 simprl φ r + C ball abs r y k x B k x R C < r k
51 50 rexrd φ r + C ball abs r y k x B k x R C < r k *
52 36 a1i φ r + C ball abs r y k x B k x R C < r +∞ *
53 50 ltpnfd φ r + C ball abs r y k x B k x R C < r k < +∞
54 ubioc1 k * +∞ * k < +∞ +∞ k +∞
55 51 52 53 54 syl3anc φ r + C ball abs r y k x B k x R C < r +∞ k +∞
56 14 ad2antrr φ r + C ball abs r y k x B k x R C < r +∞ A
57 55 56 elind φ r + C ball abs r y k x B k x R C < r +∞ k +∞ A
58 simplr φ r + C ball abs r y k x B k
59 58 rexrd φ r + C ball abs r y k x B k *
60 elioc1 k * +∞ * x k +∞ x * k < x x +∞
61 59 36 60 sylancl φ r + C ball abs r y k x B x k +∞ x * k < x x +∞
62 simp2 x * k < x x +∞ k < x
63 61 62 biimtrdi φ r + C ball abs r y k x B x k +∞ k < x
64 2 ad2antrr φ r + C ball abs r y k B
65 64 sselda φ r + C ball abs r y k x B x
66 ltle k x k < x k x
67 58 65 66 syl2anc φ r + C ball abs r y k x B k < x k x
68 63 67 syld φ r + C ball abs r y k x B x k +∞ k x
69 21 a1i φ r + C ball abs r y k x B abs ∞Met
70 simprl φ r + C ball abs r y r +
71 70 ad2antrr φ r + C ball abs r y k x B r +
72 rpxr r + r *
73 71 72 syl φ r + C ball abs r y k x B r *
74 17 ad3antrrr φ r + C ball abs r y k x B C
75 28 ad2antrr φ r + C ball abs r y k x B R
76 75 r19.21bi φ r + C ball abs r y k x B R
77 elbl3 abs ∞Met r * C R R C ball abs r R abs C < r
78 69 73 74 76 77 syl22anc φ r + C ball abs r y k x B R C ball abs r R abs C < r
79 eqid abs = abs
80 79 cnmetdval R C R abs C = R C
81 76 74 80 syl2anc φ r + C ball abs r y k x B R abs C = R C
82 81 breq1d φ r + C ball abs r y k x B R abs C < r R C < r
83 78 82 bitrd φ r + C ball abs r y k x B R C ball abs r R C < r
84 83 biimprd φ r + C ball abs r y k x B R C < r R C ball abs r
85 68 84 imim12d φ r + C ball abs r y k x B k x R C < r x k +∞ R C ball abs r
86 85 ralimdva φ r + C ball abs r y k x B k x R C < r x B x k +∞ R C ball abs r
87 86 impr φ r + C ball abs r y k x B k x R C < r x B x k +∞ R C ball abs r
88 17 ad2antrr φ r + C ball abs r y k x B k x R C < r C
89 simplrl φ r + C ball abs r y k x B k x R C < r r +
90 blcntr abs ∞Met C r + C C ball abs r
91 21 88 89 90 mp3an2i φ r + C ball abs r y k x B k x R C < r C C ball abs r
92 91 a1d φ r + C ball abs r y k x B k x R C < r +∞ k +∞ C C ball abs r
93 eleq1 x = +∞ x k +∞ +∞ k +∞
94 4 eleq1d x = +∞ R C ball abs r C C ball abs r
95 93 94 imbi12d x = +∞ x k +∞ R C ball abs r +∞ k +∞ C C ball abs r
96 11 95 ralsn x +∞ x k +∞ R C ball abs r +∞ k +∞ C C ball abs r
97 92 96 sylibr φ r + C ball abs r y k x B k x R C < r x +∞ x k +∞ R C ball abs r
98 ralunb x B +∞ x k +∞ R C ball abs r x B x k +∞ R C ball abs r x +∞ x k +∞ R C ball abs r
99 87 97 98 sylanbrc φ r + C ball abs r y k x B k x R C < r x B +∞ x k +∞ R C ball abs r
100 1 ad2antrr φ r + C ball abs r y k x B k x R C < r A = B +∞
101 99 100 raleqtrrdv φ r + C ball abs r y k x B k x R C < r x A x k +∞ R C ball abs r
102 ss2rab x A | x k +∞ x A | R C ball abs r x A x k +∞ R C ball abs r
103 101 102 sylibr φ r + C ball abs r y k x B k x R C < r x A | x k +∞ x A | R C ball abs r
104 incom k +∞ A = A k +∞
105 dfin5 A k +∞ = x A | x k +∞
106 104 105 eqtri k +∞ A = x A | x k +∞
107 9 mptpreima x A R -1 C ball abs r = x A | R C ball abs r
108 103 106 107 3sstr4g φ r + C ball abs r y k x B k x R C < r k +∞ A x A R -1 C ball abs r
109 funmpt Fun x A R
110 inss2 k +∞ A A
111 7 ad2antrr φ r + C ball abs r y k x B k x R C < r x A R : A
112 111 fdmd φ r + C ball abs r y k x B k x R C < r dom x A R = A
113 110 112 sseqtrrid φ r + C ball abs r y k x B k x R C < r k +∞ A dom x A R
114 funimass3 Fun x A R k +∞ A dom x A R x A R k +∞ A C ball abs r k +∞ A x A R -1 C ball abs r
115 109 113 114 sylancr φ r + C ball abs r y k x B k x R C < r x A R k +∞ A C ball abs r k +∞ A x A R -1 C ball abs r
116 108 115 mpbird φ r + C ball abs r y k x B k x R C < r x A R k +∞ A C ball abs r
117 simplrr φ r + C ball abs r y k x B k x R C < r C ball abs r y
118 116 117 sstrd φ r + C ball abs r y k x B k x R C < r x A R k +∞ A y
119 eleq2 z = k +∞ A +∞ z +∞ k +∞ A
120 imaeq2 z = k +∞ A x A R z = x A R k +∞ A
121 120 sseq1d z = k +∞ A x A R z y x A R k +∞ A y
122 119 121 anbi12d z = k +∞ A +∞ z x A R z y +∞ k +∞ A x A R k +∞ A y
123 122 rspcev k +∞ A K +∞ k +∞ A x A R k +∞ A y z K +∞ z x A R z y
124 49 57 118 123 syl12anc φ r + C ball abs r y k x B k x R C < r z K +∞ z x A R z y
125 124 rexlimdvaa φ r + C ball abs r y k x B k x R C < r z K +∞ z x A R z y
126 125 adantlr φ x B R C r + C ball abs r y k x B k x R C < r z K +∞ z x A R z y
127 32 126 mpd φ x B R C r + C ball abs r y z K +∞ z x A R z y
128 127 rexlimdvaa φ x B R C r + C ball abs r y z K +∞ z x A R z y
129 24 128 syl5 φ x B R C y J C y z K +∞ z x A R z y
130 129 expdimp φ x B R C y J C y z K +∞ z x A R z y
131 20 130 sylbid φ x B R C y J x A R +∞ y z K +∞ z x A R z y
132 131 ralrimiva φ x B R C y J x A R +∞ y z K +∞ z x A R z y
133 letopon ordTop TopOn *
134 resttopon ordTop TopOn * A * ordTop 𝑡 A TopOn A
135 133 40 134 sylancr φ ordTop 𝑡 A TopOn A
136 6 135 eqeltrid φ K TopOn A
137 5 cnfldtopon J TopOn
138 137 a1i φ J TopOn
139 iscnp K TopOn A J TopOn +∞ A x A R K CnP J +∞ x A R : A y J x A R +∞ y z K +∞ z x A R z y
140 136 138 14 139 syl3anc φ x A R K CnP J +∞ x A R : A y J x A R +∞ y z K +∞ z x A R z y
141 140 adantr φ x B R C x A R K CnP J +∞ x A R : A y J x A R +∞ y z K +∞ z x A R z y
142 8 132 141 mpbir2and φ x B R C x A R K CnP J +∞
143 simplr φ x A R K CnP J +∞ r + x A R K CnP J +∞
144 17 ad2antrr φ x A R K CnP J +∞ r + C
145 72 adantl φ x A R K CnP J +∞ r + r *
146 22 blopn abs ∞Met C r * C ball abs r J
147 21 144 145 146 mp3an2i φ x A R K CnP J +∞ r + C ball abs r J
148 18 ad2antrr φ x A R K CnP J +∞ r + x A R +∞ = C
149 simpr φ x A R K CnP J +∞ r + r +
150 21 144 149 90 mp3an2i φ x A R K CnP J +∞ r + C C ball abs r
151 148 150 eqeltrd φ x A R K CnP J +∞ r + x A R +∞ C ball abs r
152 cnpimaex x A R K CnP J +∞ C ball abs r J x A R +∞ C ball abs r z K +∞ z x A R z C ball abs r
153 143 147 151 152 syl3anc φ x A R K CnP J +∞ r + z K +∞ z x A R z C ball abs r
154 vex w V
155 154 inex1 w A V
156 155 a1i φ x A R K CnP J +∞ r + w ordTop w A V
157 6 eleq2i z K z ordTop 𝑡 A
158 43 ad2antrr φ x A R K CnP J +∞ r + A V
159 elrest ordTop Top A V z ordTop 𝑡 A w ordTop z = w A
160 33 158 159 sylancr φ x A R K CnP J +∞ r + z ordTop 𝑡 A w ordTop z = w A
161 157 160 bitrid φ x A R K CnP J +∞ r + z K w ordTop z = w A
162 eleq2 z = w A +∞ z +∞ w A
163 imaeq2 z = w A x A R z = x A R w A
164 163 sseq1d z = w A x A R z C ball abs r x A R w A C ball abs r
165 162 164 anbi12d z = w A +∞ z x A R z C ball abs r +∞ w A x A R w A C ball abs r
166 165 adantl φ x A R K CnP J +∞ r + z = w A +∞ z x A R z C ball abs r +∞ w A x A R w A C ball abs r
167 156 161 166 rexxfr2d φ x A R K CnP J +∞ r + z K +∞ z x A R z C ball abs r w ordTop +∞ w A x A R w A C ball abs r
168 153 167 mpbid φ x A R K CnP J +∞ r + w ordTop +∞ w A x A R w A C ball abs r
169 elinel1 +∞ w A +∞ w
170 pnfnei w ordTop +∞ w k k +∞ w
171 169 170 sylan2 w ordTop +∞ w A k k +∞ w
172 df-ima x A R w A = ran x A R w A
173 inss2 w A A
174 resmpt w A A x A R w A = x w A R
175 173 174 ax-mp x A R w A = x w A R
176 175 rneqi ran x A R w A = ran x w A R
177 172 176 eqtri x A R w A = ran x w A R
178 177 sseq1i x A R w A C ball abs r ran x w A R C ball abs r
179 dfss3 ran x w A R C ball abs r z ran x w A R z C ball abs r
180 178 179 bitri x A R w A C ball abs r z ran x w A R z C ball abs r
181 16 adantr φ r + x A R
182 ssralv w A A x A R x w A R
183 173 181 182 mpsyl φ r + x w A R
184 eqid x w A R = x w A R
185 eleq1 z = R z C ball abs r R C ball abs r
186 184 185 ralrnmptw x w A R z ran x w A R z C ball abs r x w A R C ball abs r
187 183 186 syl φ r + z ran x w A R z C ball abs r x w A R C ball abs r
188 187 biimpd φ r + z ran x w A R z C ball abs r x w A R C ball abs r
189 180 188 biimtrid φ r + x A R w A C ball abs r x w A R C ball abs r
190 simplrr φ r + k k +∞ w x B k < x k +∞ w
191 35 ad3antrrr φ r + k k +∞ w x B k < x B *
192 simprl φ r + k k +∞ w x B k < x x B
193 191 192 sseldd φ r + k k +∞ w x B k < x x *
194 simprr φ r + k k +∞ w x B k < x k < x
195 pnfge x * x +∞
196 193 195 syl φ r + k k +∞ w x B k < x x +∞
197 simplrl φ r + k k +∞ w x B k < x k
198 197 rexrd φ r + k k +∞ w x B k < x k *
199 198 36 60 sylancl φ r + k k +∞ w x B k < x x k +∞ x * k < x x +∞
200 193 194 196 199 mpbir3and φ r + k k +∞ w x B k < x x k +∞
201 190 200 sseldd φ r + k k +∞ w x B k < x x w
202 26 ad2antrr φ r + k k +∞ w B A
203 202 sselda φ r + k k +∞ w x B x A
204 203 adantrr φ r + k k +∞ w x B k < x x A
205 201 204 elind φ r + k k +∞ w x B k < x x w A
206 205 ex φ r + k k +∞ w x B k < x x w A
207 206 imim1d φ r + k k +∞ w x w A R C ball abs r x B k < x R C ball abs r
208 21 a1i φ r + k k +∞ w x B k < x abs ∞Met
209 72 adantl φ r + r *
210 209 ad2antrr φ r + k k +∞ w x B k < x r *
211 17 ad3antrrr φ r + k k +∞ w x B k < x C
212 28 ad2antrr φ r + k k +∞ w x B R
213 212 r19.21bi φ r + k k +∞ w x B R
214 213 adantrr φ r + k k +∞ w x B k < x R
215 208 210 211 214 77 syl22anc φ r + k k +∞ w x B k < x R C ball abs r R abs C < r
216 214 211 80 syl2anc φ r + k k +∞ w x B k < x R abs C = R C
217 216 breq1d φ r + k k +∞ w x B k < x R abs C < r R C < r
218 215 217 bitrd φ r + k k +∞ w x B k < x R C ball abs r R C < r
219 218 pm5.74da φ r + k k +∞ w x B k < x R C ball abs r x B k < x R C < r
220 207 219 sylibd φ r + k k +∞ w x w A R C ball abs r x B k < x R C < r
221 220 exp4a φ r + k k +∞ w x w A R C ball abs r x B k < x R C < r
222 221 ralimdv2 φ r + k k +∞ w x w A R C ball abs r x B k < x R C < r
223 222 imp φ r + k k +∞ w x w A R C ball abs r x B k < x R C < r
224 223 an32s φ r + x w A R C ball abs r k k +∞ w x B k < x R C < r
225 224 expr φ r + x w A R C ball abs r k k +∞ w x B k < x R C < r
226 225 reximdva φ r + x w A R C ball abs r k k +∞ w k x B k < x R C < r
227 226 ex φ r + x w A R C ball abs r k k +∞ w k x B k < x R C < r
228 189 227 syld φ r + x A R w A C ball abs r k k +∞ w k x B k < x R C < r
229 228 com23 φ r + k k +∞ w x A R w A C ball abs r k x B k < x R C < r
230 171 229 syl5 φ r + w ordTop +∞ w A x A R w A C ball abs r k x B k < x R C < r
231 230 impl φ r + w ordTop +∞ w A x A R w A C ball abs r k x B k < x R C < r
232 231 expimpd φ r + w ordTop +∞ w A x A R w A C ball abs r k x B k < x R C < r
233 232 rexlimdva φ r + w ordTop +∞ w A x A R w A C ball abs r k x B k < x R C < r
234 233 adantlr φ x A R K CnP J +∞ r + w ordTop +∞ w A x A R w A C ball abs r k x B k < x R C < r
235 168 234 mpd φ x A R K CnP J +∞ r + k x B k < x R C < r
236 235 ralrimiva φ x A R K CnP J +∞ r + k x B k < x R C < r
237 28 2 17 rlim2lt φ x B R C r + k x B k < x R C < r
238 237 adantr φ x A R K CnP J +∞ x B R C r + k x B k < x R C < r
239 236 238 mpbird φ x A R K CnP J +∞ x B R C
240 142 239 impbida φ x B R C x A R K CnP J +∞