Obtain all other zeroes of 3x4 + 6x3 – 2x2 – 10x – 5, if two of its zeroes

Obtain all other zeroes of 3x4 + 6x3 – 2x2 – 10x – 5, if two of its zeroes are and \sqrt { \frac { 5 }{ 3 } } and –\sqrt { \frac { 5 }{ 3 } }