Consider the change of variable

The equation becomes

This equation has solutions

Now we should find the corresponding x values by reverting the variable change:
![x^3=t \implies x = \sqrt[3]{t}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/jmblf95lu5lekuac1ck55wvvnvhkmqbgl9.png)
Using complex numbers, every number has three cubic roots, so the solutions are
![x_(1,2,3)=\sqrt[3]{(-1+√(-3))/(2)},\quad x_(4,5,6)=\sqrt[3]{(-1-√(-3))/(2)}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/s0k4y112o9d8entkh94nuwz0q1h4qyyak7.png)
So, all six roots are complex.