Answer
$ e^{-2t} \cos (3t)$
Work Step by Step
Since, $F(s)=\dfrac{s+2}{(s+2)^2+ 9}$
The inverse Laplace transform of function can be expressed as:
$F(t)=L[ \cos 3t] =\dfrac{s}{s^2+3^2} $
Now, apply the first shifting Theorem.
$f(t)= e^{-2t} \cos (3t)$