Answer
$\lim\limits_{x \to a} f(x)$ exits for each $a$, except for $a = -1$.
Work Step by Step
$ \lim\limits_{x \to -1^{-}} f(x) = 0$ and $\lim\limits_{x \to -1^{+}} f(x) = 1$
$ \lim\limits_{x \to -1^{-}} f(x) \ne \lim\limits_{x \to -1^{+}} f(x)$.
The limit of $ \lim\limits_{x \to -1} f(x)$ does not exist if $x = -1$.