Metamath Proof Explorer


Theorem numltc

Description: Comparing two decimal integers (unequal higher places). (Contributed by Mario Carneiro, 18-Feb-2014)

Ref Expression
Hypotheses numlt.1 T
numlt.2 A0
numlt.3 B0
numltc.3 C0
numltc.4 D0
numltc.5 C<T
numltc.6 A<B
Assertion numltc TA+C<TB+D

Proof

Step Hyp Ref Expression
1 numlt.1 T
2 numlt.2 A0
3 numlt.3 B0
4 numltc.3 C0
5 numltc.4 D0
6 numltc.5 C<T
7 numltc.6 A<B
8 1 2 4 1 6 numlt TA+C<TA+T
9 1 nnrei T
10 9 recni T
11 2 nn0rei A
12 11 recni A
13 ax-1cn 1
14 10 12 13 adddii TA+1=TA+T1
15 10 mulid1i T1=T
16 15 oveq2i TA+T1=TA+T
17 14 16 eqtri TA+1=TA+T
18 8 17 breqtrri TA+C<TA+1
19 nn0ltp1le A0B0A<BA+1B
20 2 3 19 mp2an A<BA+1B
21 7 20 mpbi A+1B
22 1 nngt0i 0<T
23 peano2re AA+1
24 11 23 ax-mp A+1
25 3 nn0rei B
26 24 25 9 lemul2i 0<TA+1BTA+1TB
27 22 26 ax-mp A+1BTA+1TB
28 21 27 mpbi TA+1TB
29 9 11 remulcli TA
30 4 nn0rei C
31 29 30 readdcli TA+C
32 9 24 remulcli TA+1
33 9 25 remulcli TB
34 31 32 33 ltletri TA+C<TA+1TA+1TBTA+C<TB
35 18 28 34 mp2an TA+C<TB
36 33 5 nn0addge1i TBTB+D
37 5 nn0rei D
38 33 37 readdcli TB+D
39 31 33 38 ltletri TA+C<TBTBTB+DTA+C<TB+D
40 35 36 39 mp2an TA+C<TB+D