Answer:
{0, 3, 12}
Explanation:
Put the domain values in the function and evaluate. The result is the range values.
y = 3{-2, -1, 0}^2 = 3{4, 1, 0} = {12, 3, 0}
For the given domain, the range is {0, 3, 12}.
_____
Additional comment
Neither the domain nor range values need to be put in any particular order. However, it is often convenient for them to be arranged from least to greatest.