Answer
$ \frac{9m^{2}(m+1)}{2}$
Work Step by Step
Given : $\frac{3m^{3}-3m}{4m^{2}+4m-8} \times (6m^{2}+12m)$
$= \frac{3m(m-1)(m+1)}{4(m-1)(m+2)} \times 6m(m+2)$
$= \frac{9m^{2}(m+1)}{2}$
(After dividing out the common factors (m-1) and (m+2))