Metamath Proof Explorer


Theorem iocopn

Description: A left-open right-closed interval is an open set of the standard topology restricted to an interval that contains the original interval and has the same upper bound. (Contributed by Glauco Siliprandi, 11-Dec-2019)

Ref Expression
Hypotheses iocopn.a ⊢ φ → A ∈ ℝ *
iocopn.c ⊢ φ → C ∈ ℝ *
iocopn.b ⊢ φ → B ∈ ℝ
iocopn.k ⊢ K = topGen ⁡ ran ⁡ .
iocopn.j ⊢ J = K ↾ 𝑡 A B
iocopn.alec ⊢ φ → A ≤ C
iocopn.6 ⊢ φ → B ∈ ℝ
Assertion iocopn ⊢ φ → C B ∈ J

Proof

Step Hyp Ref Expression
1 iocopn.a ⊢ φ → A ∈ ℝ *
2 iocopn.c ⊢ φ → C ∈ ℝ *
3 iocopn.b ⊢ φ → B ∈ ℝ
4 iocopn.k ⊢ K = topGen ⁡ ran ⁡ .
5 iocopn.j ⊢ J = K ↾ 𝑡 A B
6 iocopn.alec ⊢ φ → A ≤ C
7 iocopn.6 ⊢ φ → B ∈ ℝ
8 retop ⊢ topGen ⁡ ran ⁡ . ∈ Top
9 4 8 eqeltri ⊢ K ∈ Top
10 9 a1i ⊢ φ → K ∈ Top
11 ovexd ⊢ φ → A B ∈ V
12 iooretop ⊢ C +∞ ∈ topGen ⁡ ran ⁡ .
13 12 4 eleqtrri ⊢ C +∞ ∈ K
14 13 a1i ⊢ φ → C +∞ ∈ K
15 elrestr ⊢ K ∈ Top ∧ A B ∈ V ∧ C +∞ ∈ K → C +∞ ∩ A B ∈ K ↾ 𝑡 A B
16 10 11 14 15 syl3anc ⊢ φ → C +∞ ∩ A B ∈ K ↾ 𝑡 A B
17 2 adantr ⊢ φ ∧ x ∈ C +∞ ∩ A B → C ∈ ℝ *
18 3 rexrd ⊢ φ → B ∈ ℝ *
19 18 adantr ⊢ φ ∧ x ∈ C +∞ ∩ A B → B ∈ ℝ *
20 elinel1 ⊢ x ∈ C +∞ ∩ A B → x ∈ C +∞
21 elioore ⊢ x ∈ C +∞ → x ∈ ℝ
22 20 21 syl ⊢ x ∈ C +∞ ∩ A B → x ∈ ℝ
23 22 rexrd ⊢ x ∈ C +∞ ∩ A B → x ∈ ℝ *
24 23 adantl ⊢ φ ∧ x ∈ C +∞ ∩ A B → x ∈ ℝ *
25 pnfxr ⊢ +∞ ∈ ℝ *
26 25 a1i ⊢ φ ∧ x ∈ C +∞ ∩ A B → +∞ ∈ ℝ *
27 20 adantl ⊢ φ ∧ x ∈ C +∞ ∩ A B → x ∈ C +∞
28 ioogtlb ⊢ C ∈ ℝ * ∧ +∞ ∈ ℝ * ∧ x ∈ C +∞ → C < x
29 17 26 27 28 syl3anc ⊢ φ ∧ x ∈ C +∞ ∩ A B → C < x
30 1 adantr ⊢ φ ∧ x ∈ C +∞ ∩ A B → A ∈ ℝ *
31 elinel2 ⊢ x ∈ C +∞ ∩ A B → x ∈ A B
32 31 adantl ⊢ φ ∧ x ∈ C +∞ ∩ A B → x ∈ A B
33 iocleub ⊢ A ∈ ℝ * ∧ B ∈ ℝ * ∧ x ∈ A B → x ≤ B
34 30 19 32 33 syl3anc ⊢ φ ∧ x ∈ C +∞ ∩ A B → x ≤ B
35 17 19 24 29 34 eliocd ⊢ φ ∧ x ∈ C +∞ ∩ A B → x ∈ C B
36 2 adantr ⊢ φ ∧ x ∈ C B → C ∈ ℝ *
37 25 a1i ⊢ φ ∧ x ∈ C B → +∞ ∈ ℝ *
38 iocssre ⊢ C ∈ ℝ * ∧ B ∈ ℝ → C B ⊆ ℝ
39 2 7 38 syl2anc ⊢ φ → C B ⊆ ℝ
40 39 sselda ⊢ φ ∧ x ∈ C B → x ∈ ℝ
41 18 adantr ⊢ φ ∧ x ∈ C B → B ∈ ℝ *
42 simpr ⊢ φ ∧ x ∈ C B → x ∈ C B
43 iocgtlb ⊢ C ∈ ℝ * ∧ B ∈ ℝ * ∧ x ∈ C B → C < x
44 36 41 42 43 syl3anc ⊢ φ ∧ x ∈ C B → C < x
45 40 ltpnfd ⊢ φ ∧ x ∈ C B → x < +∞
46 36 37 40 44 45 eliood ⊢ φ ∧ x ∈ C B → x ∈ C +∞
47 1 adantr ⊢ φ ∧ x ∈ C B → A ∈ ℝ *
48 40 rexrd ⊢ φ ∧ x ∈ C B → x ∈ ℝ *
49 6 adantr ⊢ φ ∧ x ∈ C B → A ≤ C
50 47 36 48 49 44 xrlelttrd ⊢ φ ∧ x ∈ C B → A < x
51 iocleub ⊢ C ∈ ℝ * ∧ B ∈ ℝ * ∧ x ∈ C B → x ≤ B
52 36 41 42 51 syl3anc ⊢ φ ∧ x ∈ C B → x ≤ B
53 47 41 48 50 52 eliocd ⊢ φ ∧ x ∈ C B → x ∈ A B
54 46 53 elind ⊢ φ ∧ x ∈ C B → x ∈ C +∞ ∩ A B
55 35 54 impbida ⊢ φ → x ∈ C +∞ ∩ A B ↔ x ∈ C B
56 55 eqrdv ⊢ φ → C +∞ ∩ A B = C B
57 5 eqcomi ⊢ K ↾ 𝑡 A B = J
58 57 a1i ⊢ φ → K ↾ 𝑡 A B = J
59 16 56 58 3eltr3d ⊢ φ → C B ∈ J