# Vector

- A quantity with a magnitude and a direction. Vectors are added like arrows, end to end, and the sum (for two) is the vector from the tail of the first vector to the tip of the second.

- There are a number of different representations. Given the vector
**A**it is normal to print it in bold or it can be expressed as follows:

- are unit vectors

- If x
_{1}=0 it is customary to omit it, eg

**See also: **Cauchy-Schwarz Inequality, Dot Product, Linear Combination of Vectors, Magnitude, Orthogonal Set of Vectors, Orthonormal Set of Vectors, Scalar, Vector Space.

**Subjects: ** Algebra