Answer
$x-1$ is a factor of P(x) since when P(x) is divide by $x-1$, the remainder is 0.
(refer to the step by step part for solution)
Work Step by Step
RECALL:
The factor theorem states that $c$ is a zero of $P$ if and only if $x-c$ is a factor of $P(x)$.
$c=1$ therefore $x-c = x-1$
Divide P(x) by $x-1$ using synthetic division. (refer to the attached image below):
