Metamath Proof Explorer


Theorem decpmul

Description: Partial products algorithm for two digit multiplication. (Contributed by Steven Nguyen, 10-Dec-2022)

Ref Expression
Hypotheses decpmulnc.a A 0
decpmulnc.b B 0
decpmulnc.c C 0
decpmulnc.d D 0
decpmulnc.1 A C = E
decpmulnc.2 A D + B C = F
decpmul.3 No typesetting found for |- ( B x. D ) = ; G H with typecode |-
decpmul.4 No typesetting found for |- ( ; E G + F ) = I with typecode |-
decpmul.g G 0
decpmul.h H 0
Assertion decpmul Could not format assertion : No typesetting found for |- ( ; A B x. ; C D ) = ; I H with typecode |-

Proof

Step Hyp Ref Expression
1 decpmulnc.a A 0
2 decpmulnc.b B 0
3 decpmulnc.c C 0
4 decpmulnc.d D 0
5 decpmulnc.1 A C = E
6 decpmulnc.2 A D + B C = F
7 decpmul.3 Could not format ( B x. D ) = ; G H : No typesetting found for |- ( B x. D ) = ; G H with typecode |-
8 decpmul.4 Could not format ( ; E G + F ) = I : No typesetting found for |- ( ; E G + F ) = I with typecode |-
9 decpmul.g G 0
10 decpmul.h H 0
11 1 2 3 4 5 6 7 decpmulnc Could not format ( ; A B x. ; C D ) = ; ; E F ; G H : No typesetting found for |- ( ; A B x. ; C D ) = ; ; E F ; G H with typecode |-
12 dfdec10 Could not format ; ; E F ; G H = ( ( ; 1 0 x. ; E F ) + ; G H ) : No typesetting found for |- ; ; E F ; G H = ( ( ; 1 0 x. ; E F ) + ; G H ) with typecode |-
13 1 3 nn0mulcli A C 0
14 5 13 eqeltrri E 0
15 2 3 nn0mulcli B C 0
16 1 4 15 numcl A D + B C 0
17 6 16 eqeltrri F 0
18 14 17 deccl Could not format ; E F e. NN0 : No typesetting found for |- ; E F e. NN0 with typecode |-
19 0nn0 0 0
20 18 dec0u Could not format ( ; 1 0 x. ; E F ) = ; ; E F 0 : No typesetting found for |- ( ; 1 0 x. ; E F ) = ; ; E F 0 with typecode |-
21 eqid Could not format ; G H = ; G H : No typesetting found for |- ; G H = ; G H with typecode |-
22 14 17 9 decaddcom Could not format ( ; E F + G ) = ( ; E G + F ) : No typesetting found for |- ( ; E F + G ) = ( ; E G + F ) with typecode |-
23 22 8 eqtri Could not format ( ; E F + G ) = I : No typesetting found for |- ( ; E F + G ) = I with typecode |-
24 10 nn0cni H
25 24 addid2i 0 + H = H
26 18 19 9 10 20 21 23 25 decadd Could not format ( ( ; 1 0 x. ; E F ) + ; G H ) = ; I H : No typesetting found for |- ( ( ; 1 0 x. ; E F ) + ; G H ) = ; I H with typecode |-
27 11 12 26 3eqtri Could not format ( ; A B x. ; C D ) = ; I H : No typesetting found for |- ( ; A B x. ; C D ) = ; I H with typecode |-