Metamath Proof Explorer


Theorem mpomatmul

Description: Multiplication of two N x N matrices given in maps-to notation. (Contributed by AV, 29-Oct-2019)

Ref Expression
Hypotheses mpomatmul.a A = N Mat R
mpomatmul.b B = Base R
mpomatmul.m × ˙ = A
mpomatmul.t · ˙ = R
mpomatmul.r φ R V
mpomatmul.n φ N Fin
mpomatmul.x X = i N , j N C
mpomatmul.y Y = i N , j N E
mpomatmul.c φ i N j N C B
mpomatmul.e φ i N j N E B
mpomatmul.d φ k = i m = j D = C
mpomatmul.f φ m = i l = j F = E
mpomatmul.1 φ k N m N D U
mpomatmul.2 φ m N l N F W
Assertion mpomatmul φ X × ˙ Y = k N , l N R m N D · ˙ F

Proof

Step Hyp Ref Expression
1 mpomatmul.a A = N Mat R
2 mpomatmul.b B = Base R
3 mpomatmul.m × ˙ = A
4 mpomatmul.t · ˙ = R
5 mpomatmul.r φ R V
6 mpomatmul.n φ N Fin
7 mpomatmul.x X = i N , j N C
8 mpomatmul.y Y = i N , j N E
9 mpomatmul.c φ i N j N C B
10 mpomatmul.e φ i N j N E B
11 mpomatmul.d φ k = i m = j D = C
12 mpomatmul.f φ m = i l = j F = E
13 mpomatmul.1 φ k N m N D U
14 mpomatmul.2 φ m N l N F W
15 eqid R maMul N N N = R maMul N N N
16 1 15 matmulr N Fin R V R maMul N N N = A
17 16 3 eqtr4di N Fin R V R maMul N N N = × ˙
18 17 oveqd N Fin R V X R maMul N N N Y = X × ˙ Y
19 18 eqcomd N Fin R V X × ˙ Y = X R maMul N N N Y
20 6 5 19 syl2anc φ X × ˙ Y = X R maMul N N N Y
21 eqid Base R = Base R
22 eqid Base A = Base A
23 9 2 eleqtrdi φ i N j N C Base R
24 1 21 22 6 5 23 matbas2d φ i N , j N C Base A
25 7 24 eqeltrid φ X Base A
26 1 21 matbas2 N Fin R V Base R N × N = Base A
27 6 5 26 syl2anc φ Base R N × N = Base A
28 25 27 eleqtrrd φ X Base R N × N
29 10 2 eleqtrdi φ i N j N E Base R
30 1 21 22 6 5 29 matbas2d φ i N , j N E Base A
31 8 30 eqeltrid φ Y Base A
32 31 27 eleqtrrd φ Y Base R N × N
33 15 21 4 5 6 6 6 28 32 mamuval φ X R maMul N N N Y = k N , l N R m N k X m · ˙ m Y l
34 7 a1i φ k N l N m N X = i N , j N C
35 equcom i = k k = i
36 equcom j = m m = j
37 35 36 anbi12i i = k j = m k = i m = j
38 37 11 sylan2b φ i = k j = m D = C
39 38 eqcomd φ i = k j = m C = D
40 39 ex φ i = k j = m C = D
41 40 3ad2ant1 φ k N l N i = k j = m C = D
42 41 adantr φ k N l N m N i = k j = m C = D
43 42 imp φ k N l N m N i = k j = m C = D
44 simpl2 φ k N l N m N k N
45 simpr φ k N l N m N m N
46 simpl1 φ k N l N m N φ
47 46 44 45 13 syl3anc φ k N l N m N D U
48 34 43 44 45 47 ovmpod φ k N l N m N k X m = D
49 8 a1i φ k N l N m N Y = i N , j N E
50 equcomi i = m m = i
51 equcomi j = l l = j
52 50 51 anim12i i = m j = l m = i l = j
53 52 12 sylan2 φ i = m j = l F = E
54 53 ex φ i = m j = l F = E
55 54 3ad2ant1 φ k N l N i = m j = l F = E
56 55 adantr φ k N l N m N i = m j = l F = E
57 56 imp φ k N l N m N i = m j = l F = E
58 57 eqcomd φ k N l N m N i = m j = l E = F
59 simpl3 φ k N l N m N l N
60 46 45 59 14 syl3anc φ k N l N m N F W
61 49 58 45 59 60 ovmpod φ k N l N m N m Y l = F
62 48 61 oveq12d φ k N l N m N k X m · ˙ m Y l = D · ˙ F
63 62 mpteq2dva φ k N l N m N k X m · ˙ m Y l = m N D · ˙ F
64 63 oveq2d φ k N l N R m N k X m · ˙ m Y l = R m N D · ˙ F
65 64 mpoeq3dva φ k N , l N R m N k X m · ˙ m Y l = k N , l N R m N D · ˙ F
66 20 33 65 3eqtrd φ X × ˙ Y = k N , l N R m N D · ˙ F