\[5x^{3} - 5x = 0\]
\[5x\left( x^{2} - 1 \right) = 0\]
\[5x(x - 1)(x + 1) = 0\]
\[5x = 0;\ \ \ x - 1 = 0;\ \ \ x + 1 = 0\]
\[x = 0\ \ \ \ \ \ \ x = 1\ \ \ \ \ \ \ \ \ \ \ \ \ x = - 1\]
\[Ответ:x = 0;\ \ x = \pm 1.\]