(a)

The function is $\"\\lim_{x\\rightarrow-3}f(x)=\\infty\"$ .

As $\"x\"$ tends to $\"-3\"$ , $\"f(x)\"$ approaches to positive infinity (positive large number).

(b)

The function is $\"\\lim_{x\\rightarrow4^+}f(x)=-\\infty\"$ .

As $\"x\"$ tends to $\"4\"$ from right side, $\"f(x)\"$ approaches to negative infinity (negative large number).

(a) $\"\\lim_{x\\rightarrow-3}f(x)=\\infty\"$ means that $\"f(x)\"$ approaches to positive infinity as $\"x\"$ tends to $\"-3\"$ .

(b) $\"\\lim_{x\\rightarrow4^+}f(x)=-\\infty\"$ means that $\"f(x)\"$ approaches to negative infinity as $\"x\"$ tends to $\"4\"$ from right side.