Metamath Proof Explorer


Theorem axpre-ltadd

Description: Ordering property of addition on reals. Axiom 20 of 22 for real and complex numbers, derived from ZF set theory. Note: The more general version for extended reals is axltadd . This construction-dependent theorem should not be referenced directly; instead, use ax-pre-ltadd . (Contributed by NM, 11-May-1996) (New usage is discouraged.)

Ref Expression
Assertion axpre-ltadd A B C A < B C + A < C + B

Proof

Step Hyp Ref Expression
1 elreal A x 𝑹 x 0 𝑹 = A
2 elreal B y 𝑹 y 0 𝑹 = B
3 elreal C z 𝑹 z 0 𝑹 = C
4 breq1 x 0 𝑹 = A x 0 𝑹 < y 0 𝑹 A < y 0 𝑹
5 oveq2 x 0 𝑹 = A z 0 𝑹 + x 0 𝑹 = z 0 𝑹 + A
6 5 breq1d x 0 𝑹 = A z 0 𝑹 + x 0 𝑹 < z 0 𝑹 + y 0 𝑹 z 0 𝑹 + A < z 0 𝑹 + y 0 𝑹
7 4 6 bibi12d x 0 𝑹 = A x 0 𝑹 < y 0 𝑹 z 0 𝑹 + x 0 𝑹 < z 0 𝑹 + y 0 𝑹 A < y 0 𝑹 z 0 𝑹 + A < z 0 𝑹 + y 0 𝑹
8 breq2 y 0 𝑹 = B A < y 0 𝑹 A < B
9 oveq2 y 0 𝑹 = B z 0 𝑹 + y 0 𝑹 = z 0 𝑹 + B
10 9 breq2d y 0 𝑹 = B z 0 𝑹 + A < z 0 𝑹 + y 0 𝑹 z 0 𝑹 + A < z 0 𝑹 + B
11 8 10 bibi12d y 0 𝑹 = B A < y 0 𝑹 z 0 𝑹 + A < z 0 𝑹 + y 0 𝑹 A < B z 0 𝑹 + A < z 0 𝑹 + B
12 oveq1 z 0 𝑹 = C z 0 𝑹 + A = C + A
13 oveq1 z 0 𝑹 = C z 0 𝑹 + B = C + B
14 12 13 breq12d z 0 𝑹 = C z 0 𝑹 + A < z 0 𝑹 + B C + A < C + B
15 14 bibi2d z 0 𝑹 = C A < B z 0 𝑹 + A < z 0 𝑹 + B A < B C + A < C + B
16 ltasr z 𝑹 x < 𝑹 y z + 𝑹 x < 𝑹 z + 𝑹 y
17 16 adantr z 𝑹 x 𝑹 y 𝑹 x < 𝑹 y z + 𝑹 x < 𝑹 z + 𝑹 y
18 ltresr x 0 𝑹 < y 0 𝑹 x < 𝑹 y
19 18 a1i z 𝑹 x 𝑹 y 𝑹 x 0 𝑹 < y 0 𝑹 x < 𝑹 y
20 addresr z 𝑹 x 𝑹 z 0 𝑹 + x 0 𝑹 = z + 𝑹 x 0 𝑹
21 addresr z 𝑹 y 𝑹 z 0 𝑹 + y 0 𝑹 = z + 𝑹 y 0 𝑹
22 20 21 breqan12d z 𝑹 x 𝑹 z 𝑹 y 𝑹 z 0 𝑹 + x 0 𝑹 < z 0 𝑹 + y 0 𝑹 z + 𝑹 x 0 𝑹 < z + 𝑹 y 0 𝑹
23 22 anandis z 𝑹 x 𝑹 y 𝑹 z 0 𝑹 + x 0 𝑹 < z 0 𝑹 + y 0 𝑹 z + 𝑹 x 0 𝑹 < z + 𝑹 y 0 𝑹
24 ltresr z + 𝑹 x 0 𝑹 < z + 𝑹 y 0 𝑹 z + 𝑹 x < 𝑹 z + 𝑹 y
25 23 24 bitrdi z 𝑹 x 𝑹 y 𝑹 z 0 𝑹 + x 0 𝑹 < z 0 𝑹 + y 0 𝑹 z + 𝑹 x < 𝑹 z + 𝑹 y
26 17 19 25 3bitr4d z 𝑹 x 𝑹 y 𝑹 x 0 𝑹 < y 0 𝑹 z 0 𝑹 + x 0 𝑹 < z 0 𝑹 + y 0 𝑹
27 26 ancoms x 𝑹 y 𝑹 z 𝑹 x 0 𝑹 < y 0 𝑹 z 0 𝑹 + x 0 𝑹 < z 0 𝑹 + y 0 𝑹
28 27 3impa x 𝑹 y 𝑹 z 𝑹 x 0 𝑹 < y 0 𝑹 z 0 𝑹 + x 0 𝑹 < z 0 𝑹 + y 0 𝑹
29 1 2 3 7 11 15 28 3gencl A B C A < B C + A < C + B
30 29 biimpd A B C A < B C + A < C + B