# What is the norm of < 5 , 7 , -2 >?

Mar 13, 2016

$| | A | | = \sqrt{78}$
$\vec{A} = 5 \hat{i} + 7 \hat{j} - 2 \hat{k}$
$| | A | | = \sqrt{{5}^{2} + {7}^{2} + {\left(- 2\right)}^{2}}$
$| | A | | = \sqrt{25 + 49 + 4}$
$| | A | | = \sqrt{78}$