Metamath Proof Explorer


Theorem ltapi

Description: Ordering property of addition for positive integers. (Contributed by NM, 7-Mar-1996) (New usage is discouraged.)

Ref Expression
Assertion ltapi C 𝑵 A < 𝑵 B C + 𝑵 A < 𝑵 C + 𝑵 B

Proof

Step Hyp Ref Expression
1 dmaddpi dom + 𝑵 = 𝑵 × 𝑵
2 ltrelpi < 𝑵 𝑵 × 𝑵
3 0npi ¬ 𝑵
4 pinn A 𝑵 A ω
5 pinn B 𝑵 B ω
6 pinn C 𝑵 C ω
7 nnaord A ω B ω C ω A B C + 𝑜 A C + 𝑜 B
8 4 5 6 7 syl3an A 𝑵 B 𝑵 C 𝑵 A B C + 𝑜 A C + 𝑜 B
9 8 3expa A 𝑵 B 𝑵 C 𝑵 A B C + 𝑜 A C + 𝑜 B
10 ltpiord A 𝑵 B 𝑵 A < 𝑵 B A B
11 10 adantr A 𝑵 B 𝑵 C 𝑵 A < 𝑵 B A B
12 addclpi C 𝑵 A 𝑵 C + 𝑵 A 𝑵
13 addclpi C 𝑵 B 𝑵 C + 𝑵 B 𝑵
14 ltpiord C + 𝑵 A 𝑵 C + 𝑵 B 𝑵 C + 𝑵 A < 𝑵 C + 𝑵 B C + 𝑵 A C + 𝑵 B
15 12 13 14 syl2an C 𝑵 A 𝑵 C 𝑵 B 𝑵 C + 𝑵 A < 𝑵 C + 𝑵 B C + 𝑵 A C + 𝑵 B
16 addpiord C 𝑵 A 𝑵 C + 𝑵 A = C + 𝑜 A
17 16 adantr C 𝑵 A 𝑵 C 𝑵 B 𝑵 C + 𝑵 A = C + 𝑜 A
18 addpiord C 𝑵 B 𝑵 C + 𝑵 B = C + 𝑜 B
19 18 adantl C 𝑵 A 𝑵 C 𝑵 B 𝑵 C + 𝑵 B = C + 𝑜 B
20 17 19 eleq12d C 𝑵 A 𝑵 C 𝑵 B 𝑵 C + 𝑵 A C + 𝑵 B C + 𝑜 A C + 𝑜 B
21 15 20 bitrd C 𝑵 A 𝑵 C 𝑵 B 𝑵 C + 𝑵 A < 𝑵 C + 𝑵 B C + 𝑜 A C + 𝑜 B
22 21 anandis C 𝑵 A 𝑵 B 𝑵 C + 𝑵 A < 𝑵 C + 𝑵 B C + 𝑜 A C + 𝑜 B
23 22 ancoms A 𝑵 B 𝑵 C 𝑵 C + 𝑵 A < 𝑵 C + 𝑵 B C + 𝑜 A C + 𝑜 B
24 9 11 23 3bitr4d A 𝑵 B 𝑵 C 𝑵 A < 𝑵 B C + 𝑵 A < 𝑵 C + 𝑵 B
25 24 3impa A 𝑵 B 𝑵 C 𝑵 A < 𝑵 B C + 𝑵 A < 𝑵 C + 𝑵 B
26 1 2 3 25 ndmovord C 𝑵 A < 𝑵 B C + 𝑵 A < 𝑵 C + 𝑵 B