Metamath Proof Explorer


Theorem nnmord

Description: Ordering property of multiplication. Proposition 8.19 of TakeutiZaring p. 63, limited to natural numbers. (Contributed by NM, 22-Jan-1996) (Revised by Mario Carneiro, 15-Nov-2014)

Ref Expression
Assertion nnmord AωBωCωABCC𝑜AC𝑜B

Proof

Step Hyp Ref Expression
1 nnmordi BωCωCABC𝑜AC𝑜B
2 1 ex BωCωCABC𝑜AC𝑜B
3 2 impcomd BωCωABCC𝑜AC𝑜B
4 3 3adant1 AωBωCωABCC𝑜AC𝑜B
5 ne0i C𝑜AC𝑜BC𝑜B
6 nnm0r Bω𝑜B=
7 oveq1 C=C𝑜B=𝑜B
8 7 eqeq1d C=C𝑜B=𝑜B=
9 6 8 syl5ibrcom BωC=C𝑜B=
10 9 necon3d BωC𝑜BC
11 5 10 syl5 BωC𝑜AC𝑜BC
12 11 adantr BωCωC𝑜AC𝑜BC
13 nnord CωOrdC
14 ord0eln0 OrdCCC
15 13 14 syl CωCC
16 15 adantl BωCωCC
17 12 16 sylibrd BωCωC𝑜AC𝑜BC
18 17 3adant1 AωBωCωC𝑜AC𝑜BC
19 oveq2 A=BC𝑜A=C𝑜B
20 19 a1i AωBωCωCA=BC𝑜A=C𝑜B
21 nnmordi AωCωCBAC𝑜BC𝑜A
22 21 3adantl2 AωBωCωCBAC𝑜BC𝑜A
23 20 22 orim12d AωBωCωCA=BBAC𝑜A=C𝑜BC𝑜BC𝑜A
24 23 con3d AωBωCωC¬C𝑜A=C𝑜BC𝑜BC𝑜A¬A=BBA
25 simpl3 AωBωCωCCω
26 simpl1 AωBωCωCAω
27 nnmcl CωAωC𝑜Aω
28 25 26 27 syl2anc AωBωCωCC𝑜Aω
29 simpl2 AωBωCωCBω
30 nnmcl CωBωC𝑜Bω
31 25 29 30 syl2anc AωBωCωCC𝑜Bω
32 nnord C𝑜AωOrdC𝑜A
33 nnord C𝑜BωOrdC𝑜B
34 ordtri2 OrdC𝑜AOrdC𝑜BC𝑜AC𝑜B¬C𝑜A=C𝑜BC𝑜BC𝑜A
35 32 33 34 syl2an C𝑜AωC𝑜BωC𝑜AC𝑜B¬C𝑜A=C𝑜BC𝑜BC𝑜A
36 28 31 35 syl2anc AωBωCωCC𝑜AC𝑜B¬C𝑜A=C𝑜BC𝑜BC𝑜A
37 nnord AωOrdA
38 nnord BωOrdB
39 ordtri2 OrdAOrdBAB¬A=BBA
40 37 38 39 syl2an AωBωAB¬A=BBA
41 26 29 40 syl2anc AωBωCωCAB¬A=BBA
42 24 36 41 3imtr4d AωBωCωCC𝑜AC𝑜BAB
43 42 ex AωBωCωCC𝑜AC𝑜BAB
44 43 com23 AωBωCωC𝑜AC𝑜BCAB
45 18 44 mpdd AωBωCωC𝑜AC𝑜BAB
46 45 18 jcad AωBωCωC𝑜AC𝑜BABC
47 4 46 impbid AωBωCωABCC𝑜AC𝑜B