\[3x³ - 6x^{2} - 75x + 150 = 0\]
\[3x^{2}(x - 2) - 75 \cdot (x - 2) = 0\]
\[\left( 3x^{2} - 75 \right)(x - 2) = 0\]
\[3 \cdot \left( x^{2} - 25 \right)(x - 2) = 0\]
\[3 \cdot (x - 5)(x + 5)(x - 2) = 0\]
\[x = 5,\ \ x = - 5,\ \ x = 2\]
\[Ответ:x = 2;\ x = \pm 5.\]