| |
| | Cross product - CGAFaq |
 | | Historically, the cross product was defined (separately) by Josiah Willard Gibbs and Oliver Heaviside as a portion of the quaternion product, useful for physical applications (such as Maxwell's theory of electromagnetism). |
 | | Although, properly speaking, the cross product exists only in 3D, an occasional abuse of terminology is to refer to the “cross product” of planar vectors, a scalar result that can be interpreted as the z component of a vector in the xy plane. |
 | | For example, the cross product of two vectors is the zero vector if they are collinear, or perpendicular to their common plane if they are independent. |
| cgafaq.info /wiki/Cross_Product (446 words) |
|