Answer:
[tex]\large\boxed{Domain:\ x\in\mathbb{R}\to\text{the set of all real numbers}}[/tex]
Step-by-step explanation:
The domain of roots:
[tex]\sqrt[n]{p(x)}[/tex]
If n is an odd number, then p(x) can be any real number.
If n is an even number, then p(x) must be a non-negative number.
We have
[tex]f(x)=\sqrt[3]{2x^2-3x-9}[/tex]
n = 3 → odd number.
Therefore the domain is the set of all real numbers.