\[x^{3} - 64x = 0\]
\[x\left( x^{2} - 64 \right) = 0\]
\[x(x - 8)(x + 8) = 0\]
\[x = 0;\ \ x = 8;\ \ x = - 8.\]
\[Ответ:x = 0;\ \ x = \pm 8.\]