Metamath Proof Explorer


Theorem icoopn

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

Ref Expression
Hypotheses icoopn.a φA
icoopn.c φC*
icoopn.b φB*
icoopn.k K=topGenran.
icoopn.j J=K𝑡AB
icoopn.cleb φCB
Assertion icoopn φACJ

Proof

Step Hyp Ref Expression
1 icoopn.a φA
2 icoopn.c φC*
3 icoopn.b φB*
4 icoopn.k K=topGenran.
5 icoopn.j J=K𝑡AB
6 icoopn.cleb φCB
7 retop topGenran.Top
8 4 7 eqeltri KTop
9 8 a1i φKTop
10 ovexd φABV
11 iooretop −∞CtopGenran.
12 11 4 eleqtrri −∞CK
13 12 a1i φ−∞CK
14 elrestr KTopABV−∞CK−∞CABK𝑡AB
15 9 10 13 14 syl3anc φ−∞CABK𝑡AB
16 1 rexrd φA*
17 16 adantr φx−∞CABA*
18 2 adantr φx−∞CABC*
19 elinel1 x−∞CABx−∞C
20 elioore x−∞Cx
21 19 20 syl x−∞CABx
22 21 rexrd x−∞CABx*
23 22 adantl φx−∞CABx*
24 3 adantr φx−∞CABB*
25 elinel2 x−∞CABxAB
26 25 adantl φx−∞CABxAB
27 icogelb A*B*xABAx
28 17 24 26 27 syl3anc φx−∞CABAx
29 mnfxr −∞*
30 29 a1i φx−∞CAB−∞*
31 19 adantl φx−∞CABx−∞C
32 iooltub −∞*C*x−∞Cx<C
33 30 18 31 32 syl3anc φx−∞CABx<C
34 17 18 23 28 33 elicod φx−∞CABxAC
35 29 a1i φxAC−∞*
36 2 adantr φxACC*
37 icossre AC*AC
38 1 2 37 syl2anc φAC
39 38 sselda φxACx
40 39 mnfltd φxAC−∞<x
41 16 adantr φxACA*
42 simpr φxACxAC
43 icoltub A*C*xACx<C
44 41 36 42 43 syl3anc φxACx<C
45 35 36 39 40 44 eliood φxACx−∞C
46 3 adantr φxACB*
47 39 rexrd φxACx*
48 icogelb A*C*xACAx
49 41 36 42 48 syl3anc φxACAx
50 6 adantr φxACCB
51 47 36 46 44 50 xrltletrd φxACx<B
52 41 46 47 49 51 elicod φxACxAB
53 45 52 elind φxACx−∞CAB
54 34 53 impbida φx−∞CABxAC
55 54 eqrdv φ−∞CAB=AC
56 5 eqcomi K𝑡AB=J
57 56 a1i φK𝑡AB=J
58 15 55 57 3eltr3d φACJ