Find the derivative of the function $$f(x) = \det \left[\begin{array}{ccccc} -6 &1 &-6 &5 &9\cr 1 &0 &4 &-2 &2\cr -2 &0 &0 &1 &-6\cr x &-5 &6 &7 &7\cr -2 &0 &0 &0 &2\cr \end{array}\right].$$

$f'(x)=$ .