Answer
f is increasing in $(-\infty, \frac{-7}{2})$ and $(\frac{-7}{2},+\infty)$
Work Step by Step
The function f is undefined when x=-7/2, so -7/2 is not in the domain of f.
$f'(x)=\frac{15}{(2x+7)^{2}}$
Since $f'(x)>0$, we have: f is increasing in $(-\infty, \frac{-7}{2})$ and $(\frac{-7}{2},+\infty)$