Metamath Proof Explorer


Theorem xrge0iifiso

Description: The defined bijection from the closed unit interval onto the extended nonnegative reals is an order isomorphism. (Contributed by Thierry Arnoux, 31-Mar-2017)

Ref Expression
Hypothesis xrge0iifhmeo.1 F = x 0 1 if x = 0 +∞ log x
Assertion xrge0iifiso F Isom < , < -1 0 1 0 +∞

Proof

Step Hyp Ref Expression
1 xrge0iifhmeo.1 F = x 0 1 if x = 0 +∞ log x
2 iccssxr 0 1 *
3 xrltso < Or *
4 soss 0 1 * < Or * < Or 0 1
5 2 3 4 mp2 < Or 0 1
6 iccssxr 0 +∞ *
7 cnvso < Or * < -1 Or *
8 3 7 mpbi < -1 Or *
9 sopo < -1 Or * < -1 Po *
10 8 9 ax-mp < -1 Po *
11 poss 0 +∞ * < -1 Po * < -1 Po 0 +∞
12 6 10 11 mp2 < -1 Po 0 +∞
13 1 xrge0iifcnv F : 0 1 1-1 onto 0 +∞ F -1 = z 0 +∞ if z = +∞ 0 e z
14 13 simpli F : 0 1 1-1 onto 0 +∞
15 f1ofo F : 0 1 1-1 onto 0 +∞ F : 0 1 onto 0 +∞
16 14 15 ax-mp F : 0 1 onto 0 +∞
17 0xr 0 *
18 1xr 1 *
19 0le1 0 1
20 snunioc 0 * 1 * 0 1 0 0 1 = 0 1
21 17 18 19 20 mp3an 0 0 1 = 0 1
22 21 eleq2i w 0 0 1 w 0 1
23 elun w 0 0 1 w 0 w 0 1
24 22 23 bitr3i w 0 1 w 0 w 0 1
25 velsn w 0 w = 0
26 elunitrn z 0 1 z
27 26 adantr z 0 1 0 < z z
28 simpr z 0 1 0 < z 0 < z
29 elicc01 z 0 1 z 0 z z 1
30 29 simp3bi z 0 1 z 1
31 30 adantr z 0 1 0 < z z 1
32 1re 1
33 elioc2 0 * 1 z 0 1 z 0 < z z 1
34 17 32 33 mp2an z 0 1 z 0 < z z 1
35 27 28 31 34 syl3anbrc z 0 1 0 < z z 0 1
36 pnfxr +∞ *
37 0le0 0 0
38 ltpnf 1 1 < +∞
39 32 38 ax-mp 1 < +∞
40 iocssioo 0 * +∞ * 0 0 1 < +∞ 0 1 0 +∞
41 17 36 37 39 40 mp4an 0 1 0 +∞
42 ioorp 0 +∞ = +
43 41 42 sseqtri 0 1 +
44 43 sseli z 0 1 z +
45 relogcl z + log z
46 45 renegcld z + log z
47 ltpnf log z log z < +∞
48 46 47 syl z + log z < +∞
49 brcnvg +∞ * log z +∞ < -1 log z log z < +∞
50 36 46 49 sylancr z + +∞ < -1 log z log z < +∞
51 48 50 mpbird z + +∞ < -1 log z
52 44 51 syl z 0 1 +∞ < -1 log z
53 1 xrge0iifcv z 0 1 F z = log z
54 52 53 breqtrrd z 0 1 +∞ < -1 F z
55 35 54 syl z 0 1 0 < z +∞ < -1 F z
56 55 ex z 0 1 0 < z +∞ < -1 F z
57 breq1 w = 0 w < z 0 < z
58 fveq2 w = 0 F w = F 0
59 0elunit 0 0 1
60 iftrue x = 0 if x = 0 +∞ log x = +∞
61 pnfex +∞ V
62 60 1 61 fvmpt 0 0 1 F 0 = +∞
63 59 62 ax-mp F 0 = +∞
64 58 63 eqtrdi w = 0 F w = +∞
65 64 breq1d w = 0 F w < -1 F z +∞ < -1 F z
66 57 65 imbi12d w = 0 w < z F w < -1 F z 0 < z +∞ < -1 F z
67 56 66 syl5ibr w = 0 z 0 1 w < z F w < -1 F z
68 25 67 sylbi w 0 z 0 1 w < z F w < -1 F z
69 simpll w 0 1 z 0 1 w < z w 0 1
70 26 ad2antlr w 0 1 z 0 1 w < z z
71 0re 0
72 71 a1i w 0 1 z 0 1 w < z 0
73 43 sseli w 0 1 w +
74 73 rpred w 0 1 w
75 74 ad2antrr w 0 1 z 0 1 w < z w
76 elioc2 0 * 1 w 0 1 w 0 < w w 1
77 17 32 76 mp2an w 0 1 w 0 < w w 1
78 77 simp2bi w 0 1 0 < w
79 78 ad2antrr w 0 1 z 0 1 w < z 0 < w
80 simpr w 0 1 z 0 1 w < z w < z
81 72 75 70 79 80 lttrd w 0 1 z 0 1 w < z 0 < z
82 30 ad2antlr w 0 1 z 0 1 w < z z 1
83 70 81 82 34 syl3anbrc w 0 1 z 0 1 w < z z 0 1
84 69 83 jca w 0 1 z 0 1 w < z w 0 1 z 0 1
85 73 adantr w 0 1 z 0 1 w +
86 85 relogcld w 0 1 z 0 1 log w
87 44 adantl w 0 1 z 0 1 z +
88 87 relogcld w 0 1 z 0 1 log z
89 86 88 ltnegd w 0 1 z 0 1 log w < log z log z < log w
90 logltb w + z + w < z log w < log z
91 73 44 90 syl2an w 0 1 z 0 1 w < z log w < log z
92 negex log w V
93 negex log z V
94 92 93 brcnv log w < -1 log z log z < log w
95 94 a1i w 0 1 z 0 1 log w < -1 log z log z < log w
96 89 91 95 3bitr4d w 0 1 z 0 1 w < z log w < -1 log z
97 96 biimpd w 0 1 z 0 1 w < z log w < -1 log z
98 1 xrge0iifcv w 0 1 F w = log w
99 98 53 breqan12d w 0 1 z 0 1 F w < -1 F z log w < -1 log z
100 97 99 sylibrd w 0 1 z 0 1 w < z F w < -1 F z
101 84 80 100 sylc w 0 1 z 0 1 w < z F w < -1 F z
102 101 exp31 w 0 1 z 0 1 w < z F w < -1 F z
103 68 102 jaoi w 0 w 0 1 z 0 1 w < z F w < -1 F z
104 24 103 sylbi w 0 1 z 0 1 w < z F w < -1 F z
105 104 imp w 0 1 z 0 1 w < z F w < -1 F z
106 105 rgen2 w 0 1 z 0 1 w < z F w < -1 F z
107 soisoi < Or 0 1 < -1 Po 0 +∞ F : 0 1 onto 0 +∞ w 0 1 z 0 1 w < z F w < -1 F z F Isom < , < -1 0 1 0 +∞
108 5 12 16 106 107 mp4an F Isom < , < -1 0 1 0 +∞