Metamath Proof Explorer


Definition df-crossp

Description: Define the cross product of two 3-dimensional real coordinate vectors. Vectors are represented as functions on ( 1 ... 3 ) . (Contributed by Jiamin Zhao, 31-Jul-2026)

Ref Expression
Assertion df-crossp Could not format assertion : No typesetting found for |- crossp = ( u e. ( RR ^m ( 1 ... 3 ) ) , v e. ( RR ^m ( 1 ... 3 ) ) |-> ( k e. ( 1 ... 3 ) |-> if ( k = 1 , ( ( ( u ` 2 ) x. ( v ` 3 ) ) - ( ( u ` 3 ) x. ( v ` 2 ) ) ) , if ( k = 2 , ( ( ( u ` 3 ) x. ( v ` 1 ) ) - ( ( u ` 1 ) x. ( v ` 3 ) ) ) , ( ( ( u ` 1 ) x. ( v ` 2 ) ) - ( ( u ` 2 ) x. ( v ` 1 ) ) ) ) ) ) ) with typecode |-

Detailed syntax breakdown

Step Hyp Ref Expression
0 ccrossp Could not format crossp : No typesetting found for class crossp with typecode class
1 vu setvar u
2 cr class
3 cmap class 𝑚
4 c1 class 1
5 cfz class
6 c3 class 3
7 4 6 5 co class 1 3
8 2 7 3 co class 1 3
9 vv setvar v
10 vk setvar k
11 10 cv setvar k
12 11 4 wceq wff k = 1
13 1 cv setvar u
14 c2 class 2
15 14 13 cfv class u 2
16 cmul class ×
17 9 cv setvar v
18 6 17 cfv class v 3
19 15 18 16 co class u 2 v 3
20 cmin class
21 6 13 cfv class u 3
22 14 17 cfv class v 2
23 21 22 16 co class u 3 v 2
24 19 23 20 co class u 2 v 3 u 3 v 2
25 11 14 wceq wff k = 2
26 4 17 cfv class v 1
27 21 26 16 co class u 3 v 1
28 4 13 cfv class u 1
29 28 18 16 co class u 1 v 3
30 27 29 20 co class u 3 v 1 u 1 v 3
31 28 22 16 co class u 1 v 2
32 15 26 16 co class u 2 v 1
33 31 32 20 co class u 1 v 2 u 2 v 1
34 25 30 33 cif class if k = 2 u 3 v 1 u 1 v 3 u 1 v 2 u 2 v 1
35 12 24 34 cif class if k = 1 u 2 v 3 u 3 v 2 if k = 2 u 3 v 1 u 1 v 3 u 1 v 2 u 2 v 1
36 10 7 35 cmpt class k 1 3 if k = 1 u 2 v 3 u 3 v 2 if k = 2 u 3 v 1 u 1 v 3 u 1 v 2 u 2 v 1
37 1 9 8 8 36 cmpo class u 1 3 , v 1 3 k 1 3 if k = 1 u 2 v 3 u 3 v 2 if k = 2 u 3 v 1 u 1 v 3 u 1 v 2 u 2 v 1
38 0 37 wceq Could not format crossp = ( u e. ( RR ^m ( 1 ... 3 ) ) , v e. ( RR ^m ( 1 ... 3 ) ) |-> ( k e. ( 1 ... 3 ) |-> if ( k = 1 , ( ( ( u ` 2 ) x. ( v ` 3 ) ) - ( ( u ` 3 ) x. ( v ` 2 ) ) ) , if ( k = 2 , ( ( ( u ` 3 ) x. ( v ` 1 ) ) - ( ( u ` 1 ) x. ( v ` 3 ) ) ) , ( ( ( u ` 1 ) x. ( v ` 2 ) ) - ( ( u ` 2 ) x. ( v ` 1 ) ) ) ) ) ) ) : No typesetting found for wff crossp = ( u e. ( RR ^m ( 1 ... 3 ) ) , v e. ( RR ^m ( 1 ... 3 ) ) |-> ( k e. ( 1 ... 3 ) |-> if ( k = 1 , ( ( ( u ` 2 ) x. ( v ` 3 ) ) - ( ( u ` 3 ) x. ( v ` 2 ) ) ) , if ( k = 2 , ( ( ( u ` 3 ) x. ( v ` 1 ) ) - ( ( u ` 1 ) x. ( v ` 3 ) ) ) , ( ( ( u ` 1 ) x. ( v ` 2 ) ) - ( ( u ` 2 ) x. ( v ` 1 ) ) ) ) ) ) ) with typecode wff