## Most recent change of Vector

Edit made on September 30, 2013 by ColinWright at 16:57:39

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~~WW~~ WM

HEADERS_END

A vector quantity is one which has magnitude /and/ direction. For example, velocity is a vector quantity (whereas speed is a scalar quantity).

Vectors are commonly used to describe linear translations.

* The vector *a* = EQN:\left[\begin{matrix}a\\b\\c\end{matrix}\right] means EQN:+a units parallel to the x-axis, EQN:+b units parallel to the y-axis and EQN:+c units parallel to the z-axis.

** The magnitude of *a* is EQN:\sqrt{a^2+b^2+c^2}

~~Addition of vectors~~ Vector addition is simple: you just add together the corresponding components of each vector; it is also easy to multiply a vector by a scalar - you simply multiply each component of the vector by the scalar. Multiplying vectors, however, is not so simple; there are different ways of multiplying vectors together - the two most commonly used are the scalar product (also called the dot-product) and the vector product (also called the cross-product).