Answer
$_6P_2=30$
Work Step by Step
RECALL:
$_nP_r = \dfrac{n!}{(n-r)!}$
Use this definition to have:
$\require{cancel}
_6P_2=\dfrac{6!}{(6-2)!}
\\_6P_2=\dfrac{6!}{4!}
\\_6P_2 = \dfrac{6(5)(4!)}{4!}
\\_6P_2 = \dfrac{6(5)\cancel{(4!)}}{\cancel{4!}}
\\_6P_2=30$
