Answer
4
Work Step by Step
Reading the table,
as $x$ approaches 1 from the left,
$f(x)$ seems to approach 4,
as $x$ approaches 1 from the right,
$f(x)$ seems to approach 4.
The one sided limits seem to exist and are equal,
so we estimate that
$\displaystyle \lim_{x\rightarrow 1}f(x)=4$
