Metamath Proof Explorer


Theorem kbmul

Description: Multiplication property of outer product. (Contributed by NM, 31-May-2006) (New usage is discouraged.)

Ref Expression
Assertion kbmul A B C A B ketbra C = B ketbra A C

Proof

Step Hyp Ref Expression
1 hvmulcl A B A B
2 kbfval A B C A B ketbra C = x x ih C A B
3 1 2 stoic3 A B C A B ketbra C = x x ih C A B
4 simp2 A B C B
5 cjcl A A
6 5 3ad2ant1 A B C A
7 simp3 A B C C
8 hvmulcl A C A C
9 6 7 8 syl2anc A B C A C
10 kbfval B A C B ketbra A C = x x ih A C B
11 4 9 10 syl2anc A B C B ketbra A C = x x ih A C B
12 simpr A B C x x
13 simpl3 A B C x C
14 hicl x C x ih C
15 12 13 14 syl2anc A B C x x ih C
16 simpl1 A B C x A
17 simpl2 A B C x B
18 ax-hvmulass x ih C A B x ih C A B = x ih C A B
19 15 16 17 18 syl3anc A B C x x ih C A B = x ih C A B
20 15 16 mulcomd A B C x x ih C A = A x ih C
21 his52 A x C x ih A C = A x ih C
22 16 12 13 21 syl3anc A B C x x ih A C = A x ih C
23 20 22 eqtr4d A B C x x ih C A = x ih A C
24 23 oveq1d A B C x x ih C A B = x ih A C B
25 19 24 eqtr3d A B C x x ih C A B = x ih A C B
26 25 mpteq2dva A B C x x ih C A B = x x ih A C B
27 11 26 eqtr4d A B C B ketbra A C = x x ih C A B
28 3 27 eqtr4d A B C A B ketbra C = B ketbra A C