Theorem xrge0iifcnv 34430

Description: Define a bijection from [0, 1] onto [0, +∞]. (Contributed by Thierry Arnoux, 29-Mar-2017.)

Hypothesis

Ref	Expression
xrge0iifhmeo.1	⊢ 𝐹 = (𝑥 ∈ (0[,]1) ↦ if(𝑥 = 0, +∞, -(log‘𝑥)))

Assertion

Ref	Expression
xrge0iifcnv	⊢ (𝐹:(0[,]1)–1-1-onto→(0[,]+∞) ∧ ◡𝐹 = (𝑦 ∈ (0[,]+∞) ↦ if(𝑦 = +∞, 0, (exp‘-𝑦))))

Distinct variable group:   𝑥,𝑦

Allowed substitution hints:   𝐹(𝑥, 𝑦)

Proof of Theorem xrge0iifcnv

Step	Hyp	Ref	Expression
1		xrge0iifhmeo.1	. . 3 ⊢ 𝐹 = (𝑥 ∈ (0[,]1) ↦ if(𝑥 = 0, +∞, -(log‘𝑥)))
2		0xr 11283	. . . . . . 7 ⊢ 0 ∈ ℝ*
3		pnfxr 11290	. . . . . . 7 ⊢ +∞ ∈ ℝ*
4		0lepnf 13186	. . . . . . 7 ⊢ 0 ≤ +∞
5		ubicc2 13520	. . . . . . 7 ⊢ ((0 ∈ ℝ* ∧ +∞ ∈ ℝ* ∧ 0 ≤ +∞) → +∞ ∈ (0[,]+∞))
6	2, 3, 4, 5	mp3an 1490	. . . . . 6 ⊢ +∞ ∈ (0[,]+∞)
7	6	a1i 11	. . . . 5 ⊢ ((𝑥 ∈ (0[,]1) ∧ 𝑥 = 0) → +∞ ∈ (0[,]+∞))
8		icossicc 13491	. . . . . 6 ⊢ (0[,)+∞) ⊆ (0[,]+∞)
9		uncom 4108	. . . . . . . . . . . . . 14 ⊢ ({0} ∪ (0(,]1)) = ((0(,]1) ∪ {0})
10		1xr 11295	. . . . . . . . . . . . . . 15 ⊢ 1 ∈ ℝ*
11		0le1 11764	. . . . . . . . . . . . . . 15 ⊢ 0 ≤ 1
12		snunioc 13535	. . . . . . . . . . . . . . 15 ⊢ ((0 ∈ ℝ* ∧ 1 ∈ ℝ* ∧ 0 ≤ 1) → ({0} ∪ (0(,]1)) = (0[,]1))
13	2, 10, 11, 12	mp3an 1490	. . . . . . . . . . . . . 14 ⊢ ({0} ∪ (0(,]1)) = (0[,]1)
14	9, 13	eqtr3i 2787	. . . . . . . . . . . . 13 ⊢ ((0(,]1) ∪ {0}) = (0[,]1)
15	14	eleq2i 2854	. . . . . . . . . . . 12 ⊢ (𝑥 ∈ ((0(,]1) ∪ {0}) ↔ 𝑥 ∈ (0[,]1))
16		elun 4103	. . . . . . . . . . . 12 ⊢ (𝑥 ∈ ((0(,]1) ∪ {0}) ↔ (𝑥 ∈ (0(,]1) ∨ 𝑥 ∈ {0}))
17	15, 16	bitr3i 280	. . . . . . . . . . 11 ⊢ (𝑥 ∈ (0[,]1) ↔ (𝑥 ∈ (0(,]1) ∨ 𝑥 ∈ {0}))
18		pm2.53 865	. . . . . . . . . . 11 ⊢ ((𝑥 ∈ (0(,]1) ∨ 𝑥 ∈ {0}) → (¬ 𝑥 ∈ (0(,]1) → 𝑥 ∈ {0}))
19	17, 18	sylbi 220	. . . . . . . . . 10 ⊢ (𝑥 ∈ (0[,]1) → (¬ 𝑥 ∈ (0(,]1) → 𝑥 ∈ {0}))
20		elsni 4604	. . . . . . . . . 10 ⊢ (𝑥 ∈ {0} → 𝑥 = 0)
21	19, 20	syl6 36	. . . . . . . . 9 ⊢ (𝑥 ∈ (0[,]1) → (¬ 𝑥 ∈ (0(,]1) → 𝑥 = 0))
22	21	con1d 146	. . . . . . . 8 ⊢ (𝑥 ∈ (0[,]1) → (¬ 𝑥 = 0 → 𝑥 ∈ (0(,]1)))
23	22	imp 412	. . . . . . 7 ⊢ ((𝑥 ∈ (0[,]1) ∧ ¬ 𝑥 = 0) → 𝑥 ∈ (0(,]1))
24		0le0 12369	. . . . . . . . . . . . . 14 ⊢ 0 ≤ 0
25		1re 11235	. . . . . . . . . . . . . . 15 ⊢ 1 ∈ ℝ
26		ltpnf 13173	. . . . . . . . . . . . . . 15 ⊢ (1 ∈ ℝ → 1 < +∞)
27	25, 26	ax-mp 5	. . . . . . . . . . . . . 14 ⊢ 1 < +∞
28		iocssioo 13494	. . . . . . . . . . . . . 14 ⊢ (((0 ∈ ℝ* ∧ +∞ ∈ ℝ*) ∧ (0 ≤ 0 ∧ 1 < +∞)) → (0(,]1) ⊆ (0(,)+∞))
29	2, 3, 24, 27, 28	mp4an 706	. . . . . . . . . . . . 13 ⊢ (0(,]1) ⊆ (0(,)+∞)
30		ioorp 13480	. . . . . . . . . . . . 13 ⊢ (0(,)+∞) = ℝ+
31	29, 30	sseqtri 3982	. . . . . . . . . . . 12 ⊢ (0(,]1) ⊆ ℝ+
32	31	sseli 3930	. . . . . . . . . . 11 ⊢ (𝑥 ∈ (0(,]1) → 𝑥 ∈ ℝ+)
33	32	relogcld 26858	. . . . . . . . . 10 ⊢ (𝑥 ∈ (0(,]1) → (log‘𝑥) ∈ ℝ)
34	33	renegcld 11668	. . . . . . . . 9 ⊢ (𝑥 ∈ (0(,]1) → -(log‘𝑥) ∈ ℝ)
35	34	rexrd 11286	. . . . . . . 8 ⊢ (𝑥 ∈ (0(,]1) → -(log‘𝑥) ∈ ℝ*)
36		elioc1 13442	. . . . . . . . . . . . 13 ⊢ ((0 ∈ ℝ* ∧ 1 ∈ ℝ*) → (𝑥 ∈ (0(,]1) ↔ (𝑥 ∈ ℝ* ∧ 0 < 𝑥 ∧ 𝑥 ≤ 1)))
37	2, 10, 36	mp2an 705	. . . . . . . . . . . 12 ⊢ (𝑥 ∈ (0(,]1) ↔ (𝑥 ∈ ℝ* ∧ 0 < 𝑥 ∧ 𝑥 ≤ 1))
38	37	simp3bi 1165	. . . . . . . . . . 11 ⊢ (𝑥 ∈ (0(,]1) → 𝑥 ≤ 1)
39		1rp 13048	. . . . . . . . . . . . 13 ⊢ 1 ∈ ℝ+
40	39	a1i 11	. . . . . . . . . . . 12 ⊢ (𝑥 ∈ (0(,]1) → 1 ∈ ℝ+)
41	32, 40	logled 26862	. . . . . . . . . . 11 ⊢ (𝑥 ∈ (0(,]1) → (𝑥 ≤ 1 ↔ (log‘𝑥) ≤ (log‘1)))
42	38, 41	mpbid 235	. . . . . . . . . 10 ⊢ (𝑥 ∈ (0(,]1) → (log‘𝑥) ≤ (log‘1))
43		log1 26820	. . . . . . . . . 10 ⊢ (log‘1) = 0
44	42, 43	breqtrdi 5150	. . . . . . . . 9 ⊢ (𝑥 ∈ (0(,]1) → (log‘𝑥) ≤ 0)
45	33	le0neg1d 11812	. . . . . . . . 9 ⊢ (𝑥 ∈ (0(,]1) → ((log‘𝑥) ≤ 0 ↔ 0 ≤ -(log‘𝑥)))
46	44, 45	mpbid 235	. . . . . . . 8 ⊢ (𝑥 ∈ (0(,]1) → 0 ≤ -(log‘𝑥))
47		ltpnf 13173	. . . . . . . . 9 ⊢ (-(log‘𝑥) ∈ ℝ → -(log‘𝑥) < +∞)
48	34, 47	syl 18	. . . . . . . 8 ⊢ (𝑥 ∈ (0(,]1) → -(log‘𝑥) < +∞)
49		elico1 13443	. . . . . . . . 9 ⊢ ((0 ∈ ℝ* ∧ +∞ ∈ ℝ*) → (-(log‘𝑥) ∈ (0[,)+∞) ↔ (-(log‘𝑥) ∈ ℝ* ∧ 0 ≤ -(log‘𝑥) ∧ -(log‘𝑥) < +∞)))
50	2, 3, 49	mp2an 705	. . . . . . . 8 ⊢ (-(log‘𝑥) ∈ (0[,)+∞) ↔ (-(log‘𝑥) ∈ ℝ* ∧ 0 ≤ -(log‘𝑥) ∧ -(log‘𝑥) < +∞))
51	35, 46, 48, 50	syl3anbrc 1362	. . . . . . 7 ⊢ (𝑥 ∈ (0(,]1) → -(log‘𝑥) ∈ (0[,)+∞))
52	23, 51	syl 18	. . . . . 6 ⊢ ((𝑥 ∈ (0[,]1) ∧ ¬ 𝑥 = 0) → -(log‘𝑥) ∈ (0[,)+∞))
53	8, 52	sselid 3932	. . . . 5 ⊢ ((𝑥 ∈ (0[,]1) ∧ ¬ 𝑥 = 0) → -(log‘𝑥) ∈ (0[,]+∞))
54	7, 53	ifclda 4521	. . . 4 ⊢ (𝑥 ∈ (0[,]1) → if(𝑥 = 0, +∞, -(log‘𝑥)) ∈ (0[,]+∞))
55	54	adantl 487	. . 3 ⊢ ((⊤ ∧ 𝑥 ∈ (0[,]1)) → if(𝑥 = 0, +∞, -(log‘𝑥)) ∈ (0[,]+∞))
56		0elunit 13524	. . . . . 6 ⊢ 0 ∈ (0[,]1)
57	56	a1i 11	. . . . 5 ⊢ ((𝑦 ∈ (0[,]+∞) ∧ 𝑦 = +∞) → 0 ∈ (0[,]1))
58		iocssicc 13492	. . . . . 6 ⊢ (0(,]1) ⊆ (0[,]1)
59		snunico 13534	. . . . . . . . . . . . . 14 ⊢ ((0 ∈ ℝ* ∧ +∞ ∈ ℝ* ∧ 0 ≤ +∞) → ((0[,)+∞) ∪ {+∞}) = (0[,]+∞))
60	2, 3, 4, 59	mp3an 1490	. . . . . . . . . . . . 13 ⊢ ((0[,)+∞) ∪ {+∞}) = (0[,]+∞)
61	60	eleq2i 2854	. . . . . . . . . . . 12 ⊢ (𝑦 ∈ ((0[,)+∞) ∪ {+∞}) ↔ 𝑦 ∈ (0[,]+∞))
62		elun 4103	. . . . . . . . . . . 12 ⊢ (𝑦 ∈ ((0[,)+∞) ∪ {+∞}) ↔ (𝑦 ∈ (0[,)+∞) ∨ 𝑦 ∈ {+∞}))
63	61, 62	bitr3i 280	. . . . . . . . . . 11 ⊢ (𝑦 ∈ (0[,]+∞) ↔ (𝑦 ∈ (0[,)+∞) ∨ 𝑦 ∈ {+∞}))
64		pm2.53 865	. . . . . . . . . . 11 ⊢ ((𝑦 ∈ (0[,)+∞) ∨ 𝑦 ∈ {+∞}) → (¬ 𝑦 ∈ (0[,)+∞) → 𝑦 ∈ {+∞}))
65	63, 64	sylbi 220	. . . . . . . . . 10 ⊢ (𝑦 ∈ (0[,]+∞) → (¬ 𝑦 ∈ (0[,)+∞) → 𝑦 ∈ {+∞}))
66		elsni 4604	. . . . . . . . . 10 ⊢ (𝑦 ∈ {+∞} → 𝑦 = +∞)
67	65, 66	syl6 36	. . . . . . . . 9 ⊢ (𝑦 ∈ (0[,]+∞) → (¬ 𝑦 ∈ (0[,)+∞) → 𝑦 = +∞))
68	67	con1d 146	. . . . . . . 8 ⊢ (𝑦 ∈ (0[,]+∞) → (¬ 𝑦 = +∞ → 𝑦 ∈ (0[,)+∞)))
69	68	imp 412	. . . . . . 7 ⊢ ((𝑦 ∈ (0[,]+∞) ∧ ¬ 𝑦 = +∞) → 𝑦 ∈ (0[,)+∞))
70		rge0ssre 13511	. . . . . . . . . . . 12 ⊢ (0[,)+∞) ⊆ ℝ
71	70	sseli 3930	. . . . . . . . . . 11 ⊢ (𝑦 ∈ (0[,)+∞) → 𝑦 ∈ ℝ)
72	71	renegcld 11668	. . . . . . . . . 10 ⊢ (𝑦 ∈ (0[,)+∞) → -𝑦 ∈ ℝ)
73	72	reefcld 16178	. . . . . . . . 9 ⊢ (𝑦 ∈ (0[,)+∞) → (exp‘-𝑦) ∈ ℝ)
74	73	rexrd 11286	. . . . . . . 8 ⊢ (𝑦 ∈ (0[,)+∞) → (exp‘-𝑦) ∈ ℝ*)
75		efgt0 16195	. . . . . . . . 9 ⊢ (-𝑦 ∈ ℝ → 0 < (exp‘-𝑦))
76	72, 75	syl 18	. . . . . . . 8 ⊢ (𝑦 ∈ (0[,)+∞) → 0 < (exp‘-𝑦))
77		elico1 13443	. . . . . . . . . . . . 13 ⊢ ((0 ∈ ℝ* ∧ +∞ ∈ ℝ*) → (𝑦 ∈ (0[,)+∞) ↔ (𝑦 ∈ ℝ* ∧ 0 ≤ 𝑦 ∧ 𝑦 < +∞)))
78	2, 3, 77	mp2an 705	. . . . . . . . . . . 12 ⊢ (𝑦 ∈ (0[,)+∞) ↔ (𝑦 ∈ ℝ* ∧ 0 ≤ 𝑦 ∧ 𝑦 < +∞))
79	78	simp2bi 1164	. . . . . . . . . . 11 ⊢ (𝑦 ∈ (0[,)+∞) → 0 ≤ 𝑦)
80	71	le0neg2d 11813	. . . . . . . . . . 11 ⊢ (𝑦 ∈ (0[,)+∞) → (0 ≤ 𝑦 ↔ -𝑦 ≤ 0))
81	79, 80	mpbid 235	. . . . . . . . . 10 ⊢ (𝑦 ∈ (0[,)+∞) → -𝑦 ≤ 0)
82		0re 11237	. . . . . . . . . . 11 ⊢ 0 ∈ ℝ
83		efle 16210	. . . . . . . . . . 11 ⊢ ((-𝑦 ∈ ℝ ∧ 0 ∈ ℝ) → (-𝑦 ≤ 0 ↔ (exp‘-𝑦) ≤ (exp‘0)))
84	72, 82, 83	sylancl 598	. . . . . . . . . 10 ⊢ (𝑦 ∈ (0[,)+∞) → (-𝑦 ≤ 0 ↔ (exp‘-𝑦) ≤ (exp‘0)))
85	81, 84	mpbid 235	. . . . . . . . 9 ⊢ (𝑦 ∈ (0[,)+∞) → (exp‘-𝑦) ≤ (exp‘0))
86		ef0 16181	. . . . . . . . 9 ⊢ (exp‘0) = 1
87	85, 86	breqtrdi 5150	. . . . . . . 8 ⊢ (𝑦 ∈ (0[,)+∞) → (exp‘-𝑦) ≤ 1)
88		elioc1 13442	. . . . . . . . 9 ⊢ ((0 ∈ ℝ* ∧ 1 ∈ ℝ*) → ((exp‘-𝑦) ∈ (0(,]1) ↔ ((exp‘-𝑦) ∈ ℝ* ∧ 0 < (exp‘-𝑦) ∧ (exp‘-𝑦) ≤ 1)))
89	2, 10, 88	mp2an 705	. . . . . . . 8 ⊢ ((exp‘-𝑦) ∈ (0(,]1) ↔ ((exp‘-𝑦) ∈ ℝ* ∧ 0 < (exp‘-𝑦) ∧ (exp‘-𝑦) ≤ 1))
90	74, 76, 87, 89	syl3anbrc 1362	. . . . . . 7 ⊢ (𝑦 ∈ (0[,)+∞) → (exp‘-𝑦) ∈ (0(,]1))
91	69, 90	syl 18	. . . . . 6 ⊢ ((𝑦 ∈ (0[,]+∞) ∧ ¬ 𝑦 = +∞) → (exp‘-𝑦) ∈ (0(,]1))
92	58, 91	sselid 3932	. . . . 5 ⊢ ((𝑦 ∈ (0[,]+∞) ∧ ¬ 𝑦 = +∞) → (exp‘-𝑦) ∈ (0[,]1))
93	57, 92	ifclda 4521	. . . 4 ⊢ (𝑦 ∈ (0[,]+∞) → if(𝑦 = +∞, 0, (exp‘-𝑦)) ∈ (0[,]1))
94	93	adantl 487	. . 3 ⊢ ((⊤ ∧ 𝑦 ∈ (0[,]+∞)) → if(𝑦 = +∞, 0, (exp‘-𝑦)) ∈ (0[,]1))
95		eqeq2 2774	. . . . . 6 ⊢ (0 = if(𝑦 = +∞, 0, (exp‘-𝑦)) → (𝑥 = 0 ↔ 𝑥 = if(𝑦 = +∞, 0, (exp‘-𝑦))))
96	95	bibi1d 346	. . . . 5 ⊢ (0 = if(𝑦 = +∞, 0, (exp‘-𝑦)) → ((𝑥 = 0 ↔ 𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥))) ↔ (𝑥 = if(𝑦 = +∞, 0, (exp‘-𝑦)) ↔ 𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥)))))
97		eqeq2 2774	. . . . . 6 ⊢ ((exp‘-𝑦) = if(𝑦 = +∞, 0, (exp‘-𝑦)) → (𝑥 = (exp‘-𝑦) ↔ 𝑥 = if(𝑦 = +∞, 0, (exp‘-𝑦))))
98	97	bibi1d 346	. . . . 5 ⊢ ((exp‘-𝑦) = if(𝑦 = +∞, 0, (exp‘-𝑦)) → ((𝑥 = (exp‘-𝑦) ↔ 𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥))) ↔ (𝑥 = if(𝑦 = +∞, 0, (exp‘-𝑦)) ↔ 𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥)))))
99		simpr 490	. . . . . . 7 ⊢ (((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ 𝑦 = +∞) → 𝑦 = +∞)
100		iftrue 4491	. . . . . . . 8 ⊢ (𝑥 = 0 → if(𝑥 = 0, +∞, -(log‘𝑥)) = +∞)
101	100	eqeq2d 2773	. . . . . . 7 ⊢ (𝑥 = 0 → (𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥)) ↔ 𝑦 = +∞))
102	99, 101	syl5ibrcom 250	. . . . . 6 ⊢ (((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ 𝑦 = +∞) → (𝑥 = 0 → 𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥))))
103		ubico 33233	. . . . . . . . . . 11 ⊢ ((0 ∈ ℝ ∧ +∞ ∈ ℝ*) → ¬ +∞ ∈ (0[,)+∞))
104	82, 3, 103	mp2an 705	. . . . . . . . . 10 ⊢ ¬ +∞ ∈ (0[,)+∞)
105	104	nelir 3066	. . . . . . . . 9 ⊢ +∞ ∉ (0[,)+∞)
106		neleq1 3069	. . . . . . . . . 10 ⊢ (𝑦 = +∞ → (𝑦 ∉ (0[,)+∞) ↔ +∞ ∉ (0[,)+∞)))
107	106	adantl 487	. . . . . . . . 9 ⊢ (((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ 𝑦 = +∞) → (𝑦 ∉ (0[,)+∞) ↔ +∞ ∉ (0[,)+∞)))
108	105, 107	mpbiri 261	. . . . . . . 8 ⊢ (((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ 𝑦 = +∞) → 𝑦 ∉ (0[,)+∞))
109		neleq1 3069	. . . . . . . 8 ⊢ (𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥)) → (𝑦 ∉ (0[,)+∞) ↔ if(𝑥 = 0, +∞, -(log‘𝑥)) ∉ (0[,)+∞)))
110	108, 109	syl5ibcom 248	. . . . . . 7 ⊢ (((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ 𝑦 = +∞) → (𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥)) → if(𝑥 = 0, +∞, -(log‘𝑥)) ∉ (0[,)+∞)))
111		df-nel 3064	. . . . . . . 8 ⊢ (if(𝑥 = 0, +∞, -(log‘𝑥)) ∉ (0[,)+∞) ↔ ¬ if(𝑥 = 0, +∞, -(log‘𝑥)) ∈ (0[,)+∞))
112		iffalse 4494	. . . . . . . . . . . . 13 ⊢ (¬ 𝑥 = 0 → if(𝑥 = 0, +∞, -(log‘𝑥)) = -(log‘𝑥))
113	112	adantl 487	. . . . . . . . . . . 12 ⊢ ((𝑥 ∈ (0[,]1) ∧ ¬ 𝑥 = 0) → if(𝑥 = 0, +∞, -(log‘𝑥)) = -(log‘𝑥))
114	113, 52	eqeltrd 2862	. . . . . . . . . . 11 ⊢ ((𝑥 ∈ (0[,]1) ∧ ¬ 𝑥 = 0) → if(𝑥 = 0, +∞, -(log‘𝑥)) ∈ (0[,)+∞))
115	114	ex 418	. . . . . . . . . 10 ⊢ (𝑥 ∈ (0[,]1) → (¬ 𝑥 = 0 → if(𝑥 = 0, +∞, -(log‘𝑥)) ∈ (0[,)+∞)))
116	115	ad2antrr 739	. . . . . . . . 9 ⊢ (((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ 𝑦 = +∞) → (¬ 𝑥 = 0 → if(𝑥 = 0, +∞, -(log‘𝑥)) ∈ (0[,)+∞)))
117	116	con1d 146	. . . . . . . 8 ⊢ (((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ 𝑦 = +∞) → (¬ if(𝑥 = 0, +∞, -(log‘𝑥)) ∈ (0[,)+∞) → 𝑥 = 0))
118	111, 117	biimtrid 245	. . . . . . 7 ⊢ (((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ 𝑦 = +∞) → (if(𝑥 = 0, +∞, -(log‘𝑥)) ∉ (0[,)+∞) → 𝑥 = 0))
119	110, 118	syld 48	. . . . . 6 ⊢ (((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ 𝑦 = +∞) → (𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥)) → 𝑥 = 0))
120	102, 119	impbid 215	. . . . 5 ⊢ (((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ 𝑦 = +∞) → (𝑥 = 0 ↔ 𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥))))
121		eqeq2 2774	. . . . . . 7 ⊢ (+∞ = if(𝑥 = 0, +∞, -(log‘𝑥)) → (𝑦 = +∞ ↔ 𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥))))
122	121	bibi2d 345	. . . . . 6 ⊢ (+∞ = if(𝑥 = 0, +∞, -(log‘𝑥)) → ((𝑥 = (exp‘-𝑦) ↔ 𝑦 = +∞) ↔ (𝑥 = (exp‘-𝑦) ↔ 𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥)))))
123		eqeq2 2774	. . . . . . 7 ⊢ (-(log‘𝑥) = if(𝑥 = 0, +∞, -(log‘𝑥)) → (𝑦 = -(log‘𝑥) ↔ 𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥))))
124	123	bibi2d 345	. . . . . 6 ⊢ (-(log‘𝑥) = if(𝑥 = 0, +∞, -(log‘𝑥)) → ((𝑥 = (exp‘-𝑦) ↔ 𝑦 = -(log‘𝑥)) ↔ (𝑥 = (exp‘-𝑦) ↔ 𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥)))))
125	82	a1i 11	. . . . . . . . . . . 12 ⊢ ((𝑦 ∈ (0[,]+∞) ∧ ¬ 𝑦 = +∞) → 0 ∈ ℝ)
126	69, 76	syl 18	. . . . . . . . . . . 12 ⊢ ((𝑦 ∈ (0[,]+∞) ∧ ¬ 𝑦 = +∞) → 0 < (exp‘-𝑦))
127	125, 126	ltned 11373	. . . . . . . . . . 11 ⊢ ((𝑦 ∈ (0[,]+∞) ∧ ¬ 𝑦 = +∞) → 0 ≠ (exp‘-𝑦))
128	127	adantll 727	. . . . . . . . . 10 ⊢ (((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ ¬ 𝑦 = +∞) → 0 ≠ (exp‘-𝑦))
129	128	neneqd 2962	. . . . . . . . 9 ⊢ (((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ ¬ 𝑦 = +∞) → ¬ 0 = (exp‘-𝑦))
130		eqeq1 2766	. . . . . . . . . 10 ⊢ (𝑥 = 0 → (𝑥 = (exp‘-𝑦) ↔ 0 = (exp‘-𝑦)))
131	130	notbid 321	. . . . . . . . 9 ⊢ (𝑥 = 0 → (¬ 𝑥 = (exp‘-𝑦) ↔ ¬ 0 = (exp‘-𝑦)))
132	129, 131	syl5ibrcom 250	. . . . . . . 8 ⊢ (((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ ¬ 𝑦 = +∞) → (𝑥 = 0 → ¬ 𝑥 = (exp‘-𝑦)))
133	132	imp 412	. . . . . . 7 ⊢ ((((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ ¬ 𝑦 = +∞) ∧ 𝑥 = 0) → ¬ 𝑥 = (exp‘-𝑦))
134		simplr 781	. . . . . . 7 ⊢ ((((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ ¬ 𝑦 = +∞) ∧ 𝑥 = 0) → ¬ 𝑦 = +∞)
135	133, 134	2falsed 379	. . . . . 6 ⊢ ((((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ ¬ 𝑦 = +∞) ∧ 𝑥 = 0) → (𝑥 = (exp‘-𝑦) ↔ 𝑦 = +∞))
136		eqcom 2769	. . . . . . . . . . 11 ⊢ (𝑥 = (exp‘-𝑦) ↔ (exp‘-𝑦) = 𝑥)
137	136	a1i 11	. . . . . . . . . 10 ⊢ ((𝑥 ∈ (0(,]1) ∧ 𝑦 ∈ (0[,)+∞)) → (𝑥 = (exp‘-𝑦) ↔ (exp‘-𝑦) = 𝑥))
138		relogeftb 26819	. . . . . . . . . . 11 ⊢ ((𝑥 ∈ ℝ+ ∧ -𝑦 ∈ ℝ) → ((log‘𝑥) = -𝑦 ↔ (exp‘-𝑦) = 𝑥))
139	32, 72, 138	syl2an 608	. . . . . . . . . 10 ⊢ ((𝑥 ∈ (0(,]1) ∧ 𝑦 ∈ (0[,)+∞)) → ((log‘𝑥) = -𝑦 ↔ (exp‘-𝑦) = 𝑥))
140	33	recnd 11264	. . . . . . . . . . 11 ⊢ (𝑥 ∈ (0(,]1) → (log‘𝑥) ∈ ℂ)
141	71	recnd 11264	. . . . . . . . . . 11 ⊢ (𝑦 ∈ (0[,)+∞) → 𝑦 ∈ ℂ)
142		negcon2 11538	. . . . . . . . . . 11 ⊢ (((log‘𝑥) ∈ ℂ ∧ 𝑦 ∈ ℂ) → ((log‘𝑥) = -𝑦 ↔ 𝑦 = -(log‘𝑥)))
143	140, 141, 142	syl2an 608	. . . . . . . . . 10 ⊢ ((𝑥 ∈ (0(,]1) ∧ 𝑦 ∈ (0[,)+∞)) → ((log‘𝑥) = -𝑦 ↔ 𝑦 = -(log‘𝑥)))
144	137, 139, 143	3bitr2d 310	. . . . . . . . 9 ⊢ ((𝑥 ∈ (0(,]1) ∧ 𝑦 ∈ (0[,)+∞)) → (𝑥 = (exp‘-𝑦) ↔ 𝑦 = -(log‘𝑥)))
145	23, 69, 144	syl2an 608	. . . . . . . 8 ⊢ (((𝑥 ∈ (0[,]1) ∧ ¬ 𝑥 = 0) ∧ (𝑦 ∈ (0[,]+∞) ∧ ¬ 𝑦 = +∞)) → (𝑥 = (exp‘-𝑦) ↔ 𝑦 = -(log‘𝑥)))
146	145	an4s 673	. . . . . . 7 ⊢ (((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ (¬ 𝑥 = 0 ∧ ¬ 𝑦 = +∞)) → (𝑥 = (exp‘-𝑦) ↔ 𝑦 = -(log‘𝑥)))
147	146	anass1rs 668	. . . . . 6 ⊢ ((((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ ¬ 𝑦 = +∞) ∧ ¬ 𝑥 = 0) → (𝑥 = (exp‘-𝑦) ↔ 𝑦 = -(log‘𝑥)))
148	122, 124, 135, 147	ifbothda 4524	. . . . 5 ⊢ (((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) ∧ ¬ 𝑦 = +∞) → (𝑥 = (exp‘-𝑦) ↔ 𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥))))
149	96, 98, 120, 148	ifbothda 4524	. . . 4 ⊢ ((𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞)) → (𝑥 = if(𝑦 = +∞, 0, (exp‘-𝑦)) ↔ 𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥))))
150	149	adantl 487	. . 3 ⊢ ((⊤ ∧ (𝑥 ∈ (0[,]1) ∧ 𝑦 ∈ (0[,]+∞))) → (𝑥 = if(𝑦 = +∞, 0, (exp‘-𝑦)) ↔ 𝑦 = if(𝑥 = 0, +∞, -(log‘𝑥))))
151	1, 55, 94, 150	f1ocnv2d 7670	. 2 ⊢ (⊤ → (𝐹:(0[,]1)–1-1-onto→(0[,]+∞) ∧ ◡𝐹 = (𝑦 ∈ (0[,]+∞) ↦ if(𝑦 = +∞, 0, (exp‘-𝑦)))))
152	151	mptru 1577	1 ⊢ (𝐹:(0[,]1)–1-1-onto→(0[,]+∞) ∧ ◡𝐹 = (𝑦 ∈ (0[,]+∞) ↦ if(𝑦 = +∞, 0, (exp‘-𝑦))))

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ↔ wb 209   ∧ wa 401   ∨ wo 861   ∧ w3a 1103   = wceq 1570  ⊤wtru 1571   ∈ wcel 2145   ≠ wne 2957   ∉ wnel 3063   ∪ cun 3900   ⊆ wss 3902  ifcif 4485  {csn 4587   class class class wbr 5107   ↦ cmpt 5190  ^◡ccnv 5658  –1-1-onto→wf1o 6536  ‘cfv 6537  (class class class)co 7416  ℂcc 11125  ℝcr 11126  0cc0 11127  1c1 11128  +∞cpnf 11267  ℝ^*cxr 11269   < clt 11270   ≤ cle 11271  -cneg 11469  ℝ⁺crp 13044  (,)cioo 13400  (,]cioc 13401  [,)cico 13402  [,]cicc 13403  expce 16151  logclog 26789

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2215  ax-ext 2734  ax-rep 5236  ax-sep 5255  ax-nul 5267  ax-pow 5334  ax-pr 5402  ax-un 7739  ax-inf2 9623  ax-cnex 11183  ax-resscn 11184  ax-1cn 11185  ax-icn 11186  ax-addcl 11187  ax-addrcl 11188  ax-mulcl 11189  ax-mulrcl 11190  ax-mulcom 11191  ax-addass 11192  ax-mulass 11193  ax-distr 11194  ax-i2m1 11195  ax-1ne0 11196  ax-1rid 11197  ax-rnegex 11198  ax-rrecex 11199  ax-cnre 11200  ax-pre-lttri 11201  ax-pre-lttrn 11202  ax-pre-ltadd 11203  ax-pre-mulgt0 11204  ax-pre-sup 11205  ax-addf 11206

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3or 1104  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2566  df-eu 2596  df-clab 2741  df-cleq 2754  df-clel 2837  df-nfc 2911  df-ne 2958  df-nel 3064  df-ral 3079  df-rex 3089  df-rmo 3367  df-reu 3368  df-rab 3415  df-v 3455  df-sbc 3743  df-csb 3851  df-dif 3905  df-un 3907  df-in 3909  df-ss 3919  df-pss 3922  df-nul 4283  df-if 4486  df-pw 4562  df-sn 4588  df-pr 4590  df-tp 4592  df-op 4594  df-uni 4871  df-int 4911  df-iun 4956  df-iin 4957  df-br 5108  df-opab 5172  df-mpt 5191  df-tr 5217  df-id 5554  df-eprel 5559  df-po 5567  df-so 5568  df-fr 5612  df-se 5613  df-we 5614  df-xp 5665  df-rel 5666  df-cnv 5667  df-co 5668  df-dm 5669  df-rn 5670  df-res 5671  df-ima 5672  df-pred 6303  df-ord 6364  df-on 6365  df-lim 6366  df-suc 6367  df-iota 6493  df-fun 6539  df-fn 6540  df-f 6541  df-f1 6542  df-fo 6543  df-f1o 6544  df-fv 6545  df-isom 6546  df-riota 7373  df-ov 7419  df-oprab 7420  df-mpo 7421  df-of 7681  df-om 7866  df-1st 7989  df-2nd 7990  df-supp 8162  df-frecs 8283  df-wrecs 8314  df-recs 8363  df-rdg 8402  df-1o 8458  df-2o 8459  df-er 8699  df-map 8831  df-pm 8832  df-ixp 8908  df-en 8956  df-dom 8957  df-sdom 8958  df-fin 8959  df-fsupp 9335  df-fi 9384  df-sup 9415  df-inf 9416  df-oi 9485  df-card 9947  df-pnf 11272  df-mnf 11273  df-xr 11274  df-ltxr 11275  df-le 11276  df-sub 11470  df-neg 11471  df-div 11899  df-nn 12261  df-2 12330  df-3 12331  df-4 12332  df-5 12333  df-6 12334  df-7 12335  df-8 12336  df-9 12337  df-n0 12532  df-z 12619  df-dec 12740  df-uz 12891  df-q 13001  df-rp 13045  df-xneg 13165  df-xadd 13166  df-xmul 13167  df-ioo 13404  df-ioc 13405  df-ico 13406  df-icc 13407  df-fz 13564  df-fzo 13712  df-fl 13855  df-mod 13933  df-seq 14068  df-exp 14128  df-fac 14340  df-bc 14369  df-hash 14397  df-shft 15142  df-cj 15188  df-re 15189  df-im 15190  df-sqrt 15324  df-abs 15325  df-limsup 15560  df-clim 15577  df-rlim 15578  df-sum 15776  df-ef 16157  df-sin 16159  df-cos 16160  df-pi 16162  df-struct 17243  df-sets 17260  df-slot 17278  df-ndx 17290  df-base 17306  df-ress 17327  df-plusg 17359  df-mulr 17360  df-starv 17361  df-sca 17362  df-vsca 17363  df-ip 17364  df-tset 17365  df-ple 17366  df-ds 17368  df-unif 17369  df-hom 17370  df-cco 17371  df-rest 17511  df-topn 17512  df-0g 17530  df-gsum 17531  df-topgen 17532  df-pt 17533  df-prds 17536  df-xrs 17592  df-qtop 17597  df-imas 17598  df-xps 17600  df-mre 17674  df-mrc 17675  df-acs 17677  df-mgm 18734  df-sgrp 18823  df-mnd 18839  df-submnd 18893  df-mulg 19192  df-cntz 19445  df-cmn 19910  df-psmet 21578  df-xmet 21579  df-met 21580  df-bl 21581  df-mopn 21582  df-fbas 21583  df-fg 21584  df-cnfld 21587  df-top 23120  df-topon 23137  df-topsp 23159  df-bases 23172  df-cld 23245  df-ntr 23246  df-cls 23247  df-nei 23324  df-lp 23362  df-perf 23363  df-cn 23453  df-cnp 23454  df-haus 23541  df-tx 23789  df-hmeo 23982  df-fil 24073  df-fm 24165  df-flim 24166  df-flf 24167  df-xms 24547  df-ms 24548  df-tms 24549  df-cncf 25107  df-limc 26095  df-dv 26096  df-log 26791

This theorem is used by:  xrge0iifiso  34432  xrge0iifmhm  34436  xrge0pluscn  34437