Given,
The expression is,
![\begin{gathered} x^3=216 \\ x^3-216=0 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/6rwyk3zy1czi8ddkmb5aptox65wtyzuua8.png)
The rational theorem tells that if the polynomial has the rational 0 then it must be a fraction p/q, where p is a factor of constant term and q is the factor of leading coefficient.
The constant term 216 with factors:
![1,2,3,4,6,8,9,12,18,24,27,36,54,72,108\text{ }and\text{ }216.](https://img.qammunity.org/2023/formulas/mathematics/college/cyacgjalz5a9d5jx9w8n2j0c8kkfm9hmuj.png)
The leading coefficient is 1, with a single factor of 1.
![\begin{gathered} (p)/(q)=\frac{factor\text{ of 216}}{factor\text{ of 1}}=\pm(1)/(1),\operatorname{\pm}(2)/(1),\operatorname{\pm}(3)/(1),\operatorname{\pm}(4)/(1),\operatorname{\pm}(6)/(1),\operatorname{\pm}(8)/(1),\operatorname{\pm}(9)/(1),\operatorname{\pm}(12)/(1), \\ \operatorname{\pm}(18)/(1),\operatorname{\pm}(24)/(1),\operatorname{\pm}(27)/(1),\operatorname{\pm}(36)/(1),\operatorname{\pm}(54)/(1),\operatorname{\pm}(72)/(1),\operatorname{\pm}(108)/(1),\operatorname{\pm}(216)/(1) \end{gathered}]()
Substitute the possible roots one by one into the polynomial to find the actual roots. Start first with the whole numbers.
p(6)=0 so x=6 is a root of a polynomial p(x).
Using factor theorem to find the remaining roots,
![\begin{gathered} (x^3-216)/(x-6)=x^2+6x+36 \\ By\text{ formula method,} \\ x=(-6\pm√(36-144))/(2) \\ x=(-6\pm√(108))/(2) \\ x=(-6\pm6√(-3))/(2) \\ x=-3\pm3√(3i) \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/mgz3ceswx0wlk1vxon87atlig0dvj2w0id.png)
Hence, the roots are 6, -3-3sqrt(3)i, and -3+3sqrt(3)i. So, option A is correct.