Metamath Proof Explorer


Theorem icocncflimc

Description: Limit at the lower bound, of a continuous function defined on a left-closed right-open interval. (Contributed by Glauco Siliprandi, 11-Dec-2019)

Ref Expression
Hypotheses icocncflimc.a φA
icocncflimc.b φB*
icocncflimc.altb φA<B
icocncflimc.f φF:ABcn
Assertion icocncflimc φFAFABlimA

Proof

Step Hyp Ref Expression
1 icocncflimc.a φA
2 icocncflimc.b φB*
3 icocncflimc.altb φA<B
4 icocncflimc.f φF:ABcn
5 1 rexrd φA*
6 1 leidd φAA
7 5 2 5 6 3 elicod φAAB
8 4 7 cnlimci φFAFlimA
9 cncfrss F:ABcnAB
10 4 9 syl φAB
11 ssid
12 eqid TopOpenfld=TopOpenfld
13 eqid TopOpenfld𝑡AB=TopOpenfld𝑡AB
14 eqid TopOpenfld𝑡=TopOpenfld𝑡
15 12 13 14 cncfcn ABABcn=TopOpenfld𝑡ABCnTopOpenfld𝑡
16 10 11 15 sylancl φABcn=TopOpenfld𝑡ABCnTopOpenfld𝑡
17 4 16 eleqtrd φFTopOpenfld𝑡ABCnTopOpenfld𝑡
18 12 cnfldtopon TopOpenfldTopOn
19 18 a1i φTopOpenfldTopOn
20 resttopon TopOpenfldTopOnABTopOpenfld𝑡ABTopOnAB
21 19 10 20 syl2anc φTopOpenfld𝑡ABTopOnAB
22 12 cnfldtop TopOpenfldTop
23 unicntop =TopOpenfld
24 23 restid TopOpenfldTopTopOpenfld𝑡=TopOpenfld
25 22 24 ax-mp TopOpenfld𝑡=TopOpenfld
26 25 cnfldtopon TopOpenfld𝑡TopOn
27 cncnp TopOpenfld𝑡ABTopOnABTopOpenfld𝑡TopOnFTopOpenfld𝑡ABCnTopOpenfld𝑡F:ABxABFTopOpenfld𝑡ABCnPTopOpenfld𝑡x
28 21 26 27 sylancl φFTopOpenfld𝑡ABCnTopOpenfld𝑡F:ABxABFTopOpenfld𝑡ABCnPTopOpenfld𝑡x
29 17 28 mpbid φF:ABxABFTopOpenfld𝑡ABCnPTopOpenfld𝑡x
30 29 simpld φF:AB
31 ioossico ABAB
32 31 a1i φABAB
33 eqid TopOpenfld𝑡ABA=TopOpenfld𝑡ABA
34 1 recnd φA
35 23 ntrtop TopOpenfldTopintTopOpenfld=
36 22 35 ax-mp intTopOpenfld=
37 undif ABABAB=
38 10 37 sylib φABAB=
39 38 eqcomd φ=ABAB
40 39 fveq2d φintTopOpenfld=intTopOpenfldABAB
41 36 40 eqtr3id φ=intTopOpenfldABAB
42 34 41 eleqtrd φAintTopOpenfldABAB
43 42 7 elind φAintTopOpenfldABABAB
44 22 a1i φTopOpenfldTop
45 ssid ABAB
46 45 a1i φABAB
47 23 13 restntr TopOpenfldTopABABABintTopOpenfld𝑡ABAB=intTopOpenfldABABAB
48 44 10 46 47 syl3anc φintTopOpenfld𝑡ABAB=intTopOpenfldABABAB
49 43 48 eleqtrrd φAintTopOpenfld𝑡ABAB
50 7 snssd φAAB
51 ssequn2 AABABA=AB
52 50 51 sylib φABA=AB
53 52 eqcomd φAB=ABA
54 53 oveq2d φTopOpenfld𝑡AB=TopOpenfld𝑡ABA
55 54 fveq2d φintTopOpenfld𝑡AB=intTopOpenfld𝑡ABA
56 snunioo1 A*B*A<BABA=AB
57 5 2 3 56 syl3anc φABA=AB
58 57 eqcomd φAB=ABA
59 55 58 fveq12d φintTopOpenfld𝑡ABAB=intTopOpenfld𝑡ABAABA
60 49 59 eleqtrd φAintTopOpenfld𝑡ABAABA
61 30 32 10 12 33 60 limcres φFABlimA=FlimA
62 8 61 eleqtrrd φFAFABlimA