The domain of the function is given. find the range.

f(x) = 2x - 1

domain: {-2, 0, 2, 4}

The range is how much it spans in f(x), f(x) is a line, it has no max/min, so it's enough to substitute the least and greatest values of your domain:

f(-2) = -5, f(4)=7,

Range = [-5,7]

The range is found by plugging in the values of the domain into 2x - 1
So for x =  -2, f(x) = 2(-2) - 1  = -5

The range will consist of -5 and the other 3 values of f(x) found  for  x = 0, x=2 and x=4.

The answer would be quadratic trinomial

I'm sure the answer is a