Answer
$v=2i-4j$ and $||v||=2 \sqrt {5}$
Work Step by Step
Let us consider that a vector $v$ is given by: $v=pi+qj$
The magnitude of a vector can be determined using the formula
$||v||=\sqrt{p^2+q^2} ~~~(1)$
We have: $v=(3-1)i+[-6-(-2)]j=2i-4j$
We will use formula (1) to obtain:
$||v||=\sqrt{(2)^2+(-4)^2}\\
=\sqrt{4+16}\\
=\sqrt{20}\\=2 \sqrt {5}$
