Answer
$V'\left( t \right) = - \frac{3}{5}{t^{ - 8/5}} + 4{t^3}$
Work Step by Step
$$\eqalign{
& V\left( t \right) = {t^{ - 3/5}} + {t^4} \cr
& {\text{Differentiate the function}} \cr
& V'\left( t \right) = \frac{d}{{dt}}\left[ {{t^{ - 3/5}} + {t^4}} \right] \cr
& {\text{Use the sum diffence rules for differentiation }} \cr
& V'\left( t \right) = \frac{d}{{dt}}\left[ {{t^{ - 3/5}}} \right] + \frac{d}{{dt}}\left[ {{t^4}} \right] \cr
& {\text{Apply the power rule: }}\frac{d}{{dt}}\left[ {{t^n}} \right] = n{t^{n - 1}} \cr
& V'\left( t \right) = - \frac{3}{5}{t^{ - 3/5 - 1}} + 4{t^{4 - 1}} \cr
& {\text{Simplify}} \cr
& V'\left( t \right) = - \frac{3}{5}{t^{ - 8/5}} + 4{t^3} \cr} $$
