Find a formula for the derivative of the function $g(x) = 4x^{2}-8$ using difference quotients:
$g'(x) = \lim\limits_{h\to0}\, [($ $) / h]$
$\qquad =$ .
(In the first answer blank, fill in the numerator of the difference quotient you use to evaluate the derivative. In the second, fill out the derivative you obtain after completing the limit calculation.)