Metamath Proof Explorer


Theorem xrge0omnd

Description: The nonnegative extended real numbers form an ordered monoid. (Contributed by Thierry Arnoux, 22-Mar-2018)

Ref Expression
Assertion xrge0omnd 𝑠*𝑠0+∞oMnd

Proof

Step Hyp Ref Expression
1 xrge0cmn 𝑠*𝑠0+∞CMnd
2 cmnmnd 𝑠*𝑠0+∞CMnd𝑠*𝑠0+∞Mnd
3 1 2 ax-mp 𝑠*𝑠0+∞Mnd
4 ovex 𝑠*𝑠0+∞V
5 xrge0base 0+∞=Base𝑠*𝑠0+∞
6 xrge0le =𝑠*𝑠0+∞
7 eliccxr x0+∞x*
8 7 xrleidd x0+∞xx
9 eliccxr y0+∞y*
10 xrletri3 x*y*x=yxyyx
11 10 biimprd x*y*xyyxx=y
12 7 9 11 syl2an x0+∞y0+∞xyyxx=y
13 eliccxr z0+∞z*
14 xrletr x*y*z*xyyzxz
15 7 9 13 14 syl3an x0+∞y0+∞z0+∞xyyzxz
16 4 5 6 8 12 15 isposi 𝑠*𝑠0+∞Poset
17 xrletri x*y*xyyx
18 7 9 17 syl2an x0+∞y0+∞xyyx
19 18 rgen2 x0+∞y0+∞xyyx
20 5 6 istos 𝑠*𝑠0+∞Toset𝑠*𝑠0+∞Posetx0+∞y0+∞xyyx
21 16 19 20 mpbir2an 𝑠*𝑠0+∞Toset
22 xleadd1a x*y*z*xyx+𝑒zy+𝑒z
23 22 ex x*y*z*xyx+𝑒zy+𝑒z
24 7 9 13 23 syl3an x0+∞y0+∞z0+∞xyx+𝑒zy+𝑒z
25 24 rgen3 x0+∞y0+∞z0+∞xyx+𝑒zy+𝑒z
26 xrge0plusg +𝑒=+𝑠*𝑠0+∞
27 5 26 6 isomnd 𝑠*𝑠0+∞oMnd𝑠*𝑠0+∞Mnd𝑠*𝑠0+∞Tosetx0+∞y0+∞z0+∞xyx+𝑒zy+𝑒z
28 3 21 25 27 mpbir3an 𝑠*𝑠0+∞oMnd