Answer
$56$
Work Step by Step
RECALL:
$g(a)$ represents the value of the function $g$ when $x=a$.
Thus, $g(3)$ represents the value of the function $g$ when $x=3$.
Substitute $3$ to $x$ in the function $g$ to obtain:
$g(3) = 2(3)^3-3^2+4(3)-1
\\g(3)=2(27)-9+12-1
\\g(3)=54-9+12-1
\\g(3)=45+12-1
\\g(3)=57-1
\\g(3)=56$