Answer
The solution set is $(-\infty,-2]\cup[1,3]$
Work Step by Step
$(x+2)(x-1)(x-3)\le0\hspace{0.7cm}{\color{blue}{\text{Given equation}}}$
The factors of the left-hand side are $x+2, x-1$ and $x-3$.
These factors are zero when $x=-2, x=1$ and $x=3$.
These numbers divide the real line into the intervals
$(-\infty,-2),(-2,1),(1,3),(3,\infty)$
From the diagram and hence the inequality involves $\le$, the endpoints of the intervals satisfy the inequality.
The solution set is $(-\infty,-2]\cup[1,3]$
