Metamath Proof Explorer


Theorem io1ii

Description: ( A (,] 1 ) is open in II . (Contributed by Zhi Wang, 9-Sep-2024)

Ref Expression
Assertion io1ii 0 A A 1 II

Proof

Step Hyp Ref Expression
1 0xr 0 *
2 lerelxr * × *
3 2 brel 0 A 0 * A *
4 3 simprd 0 A A *
5 rexr x x *
6 xrlelttr 0 * A * x * 0 A A < x 0 < x
7 xrltle 0 * x * 0 < x 0 x
8 7 3adant2 0 * A * x * 0 < x 0 x
9 6 8 syld 0 * A * x * 0 A A < x 0 x
10 1 4 5 9 mp3an3an 0 A x 0 A A < x 0 x
11 10 imp 0 A x 0 A A < x 0 x
12 11 3impdi 0 A x A < x 0 x
13 12 3expib 0 A x A < x 0 x
14 13 pm4.71d 0 A x A < x x A < x 0 x
15 14 anbi1d 0 A x A < x x 1 x A < x 0 x x 1
16 df-3an x A < x x 1 x A < x x 1
17 3anass x 0 x x 1 x 0 x x 1
18 17 anbi2i x A < x x 0 x x 1 x A < x x 0 x x 1
19 anandi x A < x 0 x x 1 x A < x x 0 x x 1
20 anass x A < x 0 x x 1 x A < x 0 x x 1
21 anass x A < x 0 x x 1 x A < x 0 x x 1
22 20 21 bitr2i x A < x 0 x x 1 x A < x 0 x x 1
23 18 19 22 3bitr2i x A < x x 0 x x 1 x A < x 0 x x 1
24 15 16 23 3bitr4g 0 A x A < x x 1 x A < x x 0 x x 1
25 1re 1
26 elioc2 A * 1 x A 1 x A < x x 1
27 4 25 26 sylancl 0 A x A 1 x A < x x 1
28 elin x A +∞ 0 1 x A +∞ x 0 1
29 elicc01 x 0 1 x 0 x x 1
30 29 anbi2i x A +∞ x 0 1 x A +∞ x 0 x x 1
31 28 30 bitri x A +∞ 0 1 x A +∞ x 0 x x 1
32 elioopnf A * x A +∞ x A < x
33 4 32 syl 0 A x A +∞ x A < x
34 33 anbi1d 0 A x A +∞ x 0 x x 1 x A < x x 0 x x 1
35 31 34 syl5bb 0 A x A +∞ 0 1 x A < x x 0 x x 1
36 24 27 35 3bitr4rd 0 A x A +∞ 0 1 x A 1
37 36 eqrdv 0 A A +∞ 0 1 = A 1
38 fvex topGen ran . V
39 ovex 0 1 V
40 iooretop A +∞ topGen ran .
41 elrestr topGen ran . V 0 1 V A +∞ topGen ran . A +∞ 0 1 topGen ran . 𝑡 0 1
42 38 39 40 41 mp3an A +∞ 0 1 topGen ran . 𝑡 0 1
43 dfii2 II = topGen ran . 𝑡 0 1
44 42 43 eleqtrri A +∞ 0 1 II
45 37 44 eqeltrrdi 0 A A 1 II