Metamath Proof Explorer


Definition df-xrh

Description: Define an embedding from the extended real number into a complete lattice. (Contributed by Thierry Arnoux, 19-Feb-2018)

Ref Expression
Assertion df-xrh *Hom = ( 𝑟 ∈ V ↦ ( 𝑥 ∈ ℝ* ↦ if ( 𝑥 ∈ ℝ , ( ( ℝHom ‘ 𝑟 ) ‘ 𝑥 ) , if ( 𝑥 = +∞ , ( ( lub ‘ 𝑟 ) ‘ ( ( ℝHom ‘ 𝑟 ) “ ℝ ) ) , ( ( glb ‘ 𝑟 ) ‘ ( ( ℝHom ‘ 𝑟 ) “ ℝ ) ) ) ) ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cxrh *Hom
1 vr 𝑟
2 cvv V
3 vx 𝑥
4 cxr *
5 3 cv 𝑥
6 cr
7 5 6 wcel 𝑥 ∈ ℝ
8 crrh ℝHom
9 1 cv 𝑟
10 9 8 cfv ( ℝHom ‘ 𝑟 )
11 5 10 cfv ( ( ℝHom ‘ 𝑟 ) ‘ 𝑥 )
12 cpnf +∞
13 5 12 wceq 𝑥 = +∞
14 club lub
15 9 14 cfv ( lub ‘ 𝑟 )
16 10 6 cima ( ( ℝHom ‘ 𝑟 ) “ ℝ )
17 16 15 cfv ( ( lub ‘ 𝑟 ) ‘ ( ( ℝHom ‘ 𝑟 ) “ ℝ ) )
18 cglb glb
19 9 18 cfv ( glb ‘ 𝑟 )
20 16 19 cfv ( ( glb ‘ 𝑟 ) ‘ ( ( ℝHom ‘ 𝑟 ) “ ℝ ) )
21 13 17 20 cif if ( 𝑥 = +∞ , ( ( lub ‘ 𝑟 ) ‘ ( ( ℝHom ‘ 𝑟 ) “ ℝ ) ) , ( ( glb ‘ 𝑟 ) ‘ ( ( ℝHom ‘ 𝑟 ) “ ℝ ) ) )
22 7 11 21 cif if ( 𝑥 ∈ ℝ , ( ( ℝHom ‘ 𝑟 ) ‘ 𝑥 ) , if ( 𝑥 = +∞ , ( ( lub ‘ 𝑟 ) ‘ ( ( ℝHom ‘ 𝑟 ) “ ℝ ) ) , ( ( glb ‘ 𝑟 ) ‘ ( ( ℝHom ‘ 𝑟 ) “ ℝ ) ) ) )
23 3 4 22 cmpt ( 𝑥 ∈ ℝ* ↦ if ( 𝑥 ∈ ℝ , ( ( ℝHom ‘ 𝑟 ) ‘ 𝑥 ) , if ( 𝑥 = +∞ , ( ( lub ‘ 𝑟 ) ‘ ( ( ℝHom ‘ 𝑟 ) “ ℝ ) ) , ( ( glb ‘ 𝑟 ) ‘ ( ( ℝHom ‘ 𝑟 ) “ ℝ ) ) ) ) )
24 1 2 23 cmpt ( 𝑟 ∈ V ↦ ( 𝑥 ∈ ℝ* ↦ if ( 𝑥 ∈ ℝ , ( ( ℝHom ‘ 𝑟 ) ‘ 𝑥 ) , if ( 𝑥 = +∞ , ( ( lub ‘ 𝑟 ) ‘ ( ( ℝHom ‘ 𝑟 ) “ ℝ ) ) , ( ( glb ‘ 𝑟 ) ‘ ( ( ℝHom ‘ 𝑟 ) “ ℝ ) ) ) ) ) )
25 0 24 wceq *Hom = ( 𝑟 ∈ V ↦ ( 𝑥 ∈ ℝ* ↦ if ( 𝑥 ∈ ℝ , ( ( ℝHom ‘ 𝑟 ) ‘ 𝑥 ) , if ( 𝑥 = +∞ , ( ( lub ‘ 𝑟 ) ‘ ( ( ℝHom ‘ 𝑟 ) “ ℝ ) ) , ( ( glb ‘ 𝑟 ) ‘ ( ( ℝHom ‘ 𝑟 ) “ ℝ ) ) ) ) ) )