Issolvi y=1/3x^3-9x

$$y = \frac { 1 } { 3 } x ^ { 3 } - 9 x$$

Solvi għal x (complex solution)

$$x=-\frac{\sqrt[3]{2}\times 3^{\frac{2}{3}}\left(1+\sqrt{3}i\right)\left(\sqrt{y^{2}-324}+y\right)^{-\frac{1}{3}}\left(-3\sqrt[3]{2}i\sqrt[6]{3}\left(\sqrt{y^{2}-324}+y\right)^{\frac{2}{3}}-\sqrt[3]{2}\times \left(3\left(\sqrt{y^{2}-324}+y\right)\right)^{\frac{2}{3}}+36\right)}{24}$$

$$x=\frac{\sqrt[3]{2}\times 3^{\frac{2}{3}}\left(\sqrt{y^{2}-324}+y\right)^{-\frac{1}{3}}\left(\sqrt[3]{2}\times \left(3\left(\sqrt{y^{2}-324}+y\right)\right)^{\frac{2}{3}}+18\right)}{6}$$

$$x=-\frac{\sqrt[3]{2}\times 3^{\frac{2}{3}}\left(-\sqrt{3}i+1\right)\left(\sqrt{y^{2}-324}+y\right)^{-\frac{1}{3}}\left(3\sqrt[3]{2}i\sqrt[6]{3}\left(\sqrt{y^{2}-324}+y\right)^{\frac{2}{3}}-\sqrt[3]{2}\times \left(3\left(\sqrt{y^{2}-324}+y\right)\right)^{\frac{2}{3}}+36\right)}{24}$$

Solvi għal y

$$y=\frac{x\left(x^{2}-27\right)}{3}$$