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 ABCA<BC+A<C+B

Proof

Step Hyp Ref Expression
1 elreal Ax𝑹x0𝑹=A
2 elreal By𝑹y0𝑹=B
3 elreal Cz𝑹z0𝑹=C
4 breq1 x0𝑹=Ax0𝑹<y0𝑹A<y0𝑹
5 oveq2 x0𝑹=Az0𝑹+x0𝑹=z0𝑹+A
6 5 breq1d x0𝑹=Az0𝑹+x0𝑹<z0𝑹+y0𝑹z0𝑹+A<z0𝑹+y0𝑹
7 4 6 bibi12d x0𝑹=Ax0𝑹<y0𝑹z0𝑹+x0𝑹<z0𝑹+y0𝑹A<y0𝑹z0𝑹+A<z0𝑹+y0𝑹
8 breq2 y0𝑹=BA<y0𝑹A<B
9 oveq2 y0𝑹=Bz0𝑹+y0𝑹=z0𝑹+B
10 9 breq2d y0𝑹=Bz0𝑹+A<z0𝑹+y0𝑹z0𝑹+A<z0𝑹+B
11 8 10 bibi12d y0𝑹=BA<y0𝑹z0𝑹+A<z0𝑹+y0𝑹A<Bz0𝑹+A<z0𝑹+B
12 oveq1 z0𝑹=Cz0𝑹+A=C+A
13 oveq1 z0𝑹=Cz0𝑹+B=C+B
14 12 13 breq12d z0𝑹=Cz0𝑹+A<z0𝑹+BC+A<C+B
15 14 bibi2d z0𝑹=CA<Bz0𝑹+A<z0𝑹+BA<BC+A<C+B
16 ltasr z𝑹x<𝑹yz+𝑹x<𝑹z+𝑹y
17 16 adantr z𝑹x𝑹y𝑹x<𝑹yz+𝑹x<𝑹z+𝑹y
18 ltresr x0𝑹<y0𝑹x<𝑹y
19 18 a1i z𝑹x𝑹y𝑹x0𝑹<y0𝑹x<𝑹y
20 addresr z𝑹x𝑹z0𝑹+x0𝑹=z+𝑹x0𝑹
21 addresr z𝑹y𝑹z0𝑹+y0𝑹=z+𝑹y0𝑹
22 20 21 breqan12d z𝑹x𝑹z𝑹y𝑹z0𝑹+x0𝑹<z0𝑹+y0𝑹z+𝑹x0𝑹<z+𝑹y0𝑹
23 22 anandis z𝑹x𝑹y𝑹z0𝑹+x0𝑹<z0𝑹+y0𝑹z+𝑹x0𝑹<z+𝑹y0𝑹
24 ltresr z+𝑹x0𝑹<z+𝑹y0𝑹z+𝑹x<𝑹z+𝑹y
25 23 24 bitrdi z𝑹x𝑹y𝑹z0𝑹+x0𝑹<z0𝑹+y0𝑹z+𝑹x<𝑹z+𝑹y
26 17 19 25 3bitr4d z𝑹x𝑹y𝑹x0𝑹<y0𝑹z0𝑹+x0𝑹<z0𝑹+y0𝑹
27 26 ancoms x𝑹y𝑹z𝑹x0𝑹<y0𝑹z0𝑹+x0𝑹<z0𝑹+y0𝑹
28 27 3impa x𝑹y𝑹z𝑹x0𝑹<y0𝑹z0𝑹+x0𝑹<z0𝑹+y0𝑹
29 1 2 3 7 11 15 28 3gencl ABCA<BC+A<C+B
30 29 biimpd ABCA<BC+A<C+B