# What is the norm of < -5 , 4 , 5 >?

Apr 10, 2018

$\sqrt{66}$

#### Explanation:

The standard (Euclidean) norm of a vector $\vec{a} = \left({a}_{1} , {a}_{2} , {a}_{3}\right)$ is

$| | \vec{a} | | = \sqrt{{a}_{1}^{2} + {a}_{2}^{2} + {a}_{3}^{2}}$

So, for the given vector, the norm is

$\sqrt{{\left(- 5\right)}^{2} + {4}^{2} + {5}^{2}} = \sqrt{66}$