plug in the 5 values in the domain
f(-2) = 2(-2)^2 - 2(-2) + 5 = 8+4+5 = 17 so first number in the range is 17.
f(-1) = 2(-1)^2 -2(-1) + 5 = 2 + 2 + 5 = 9
f(0) = 0 - 2 + 5 = 5
fond f(1) and f(2) in the same way
results are 17,9,5,5,9
so the range is {5, 9,17} (you don't repeat values)