$$0=- { x }^{ 3 } -3 { x }^{ 2 } -x+3$$
$x=\frac{9^{\frac{2}{3}}\left(\sqrt[3]{\sqrt{57}+9}+\sqrt[3]{9-\sqrt{57}}-\sqrt[3]{9}\right)}{9}\approx 0.769292354$
