Answer:
The range of the function is {1,3,5}.
Explanation:
The function is defined as

The set of all possible inputs is called domain and the set of output is called range.
In other words the possible values of x are elements of domain and the values of y are the elements of range.
Since the domain is {1,2,3} and the function is

Put x=1




Put x=2




Put x=3




Since the possible values of y are 5,3 and 1, therefore the range of the function is {1,3,5}