The Cross Product
The cross product of two vectors, c =
a × b has the following properties:
- Magnitude:   c = a b sin θ
- The direction of c is perpendicular
to the plane spanned by
a and b and is determined by the
right-hand rule.
- Non-commutative: a × b = -
b × a
- Algebraic formula:
c = a × b = (ay
bz - by a z ) +
(az bx - bz ax ) + (ax by - bx
ay )