#### Answer

$x^2(3x^2-6x-1)$

#### Work Step by Step

The greatest common factor of the coefficients 3, -6, and -1 is $1$.
The greatest common factor of $x^4,x^3$ and $x^2$ is $x^2$.
Thus, the greatest common factor of the three terms is $x^2$.
Factor out $x^2$ to obtain:
$=x^2(3x^2-6x-1)$