Let \> f(x)= \begin{cases}
x - 1, &x \le 3, \\
3 x - 7, &x > 3.
\end{cases} .

Find

(a)\> \displaystyle \lim_{x \rightarrow 3^-} f(x) :

(b)\> \displaystyle \lim_{x \rightarrow 3^+} f(x) :

(c)\> \displaystyle \lim_{x \rightarrow 3} f(x) :

Enter** I ** for \infty , ** -I ** for -\infty ,
and ** DNE ** if the limit does not exist.

Find

(a)

(b)

(c)

Enter

You can earn partial credit on this problem.