(a)
Given, $f(x) = 2x^{2} - 4x + 1$
$\therefore\ g(x) = \frac{2x^{2} - 4x + 1 - 2x^{2} - 4x - 1}{2} = - 4x$
$\therefore\int_{- 3}^{3}{g(x)dx} = - 4\int_{- 3}^{3}{x\ dx}$
$= - 4\left\lbrack \frac{x^{2}}{2} \right\rbrack_{- 3}^{3} = - 2\lbrack 9 - 9\rbrack = 0$