Solve the Polynomial Equation $$3 \mathrm { x } ^ { 3 } - \mathrm { x } ^ { 2 } - 15 \mathrm { x } + 5 = 0$$

Multiple Choice

Solve the polynomial equation. In order to obtain the first root, use synthetic division to test the possible rational
roots.
- $$3 \mathrm { x } ^ { 3 } - \mathrm { x } ^ { 2 } - 15 \mathrm { x } + 5 = 0$$

A) $\left\{ \frac { 1 } { 3 } , \sqrt { 5 } , - \sqrt { 5 } \right\}$
B) $\left\{ - \frac { 1 } { 3 } , \sqrt { 5 } , - \sqrt { 5 } \right\}$
C) $\{ 3 , \sqrt { 5 } , - \sqrt { 5 } \}$
D) $\{ - 3 , \sqrt { 5 } , - \sqrt { 5 } \}$