What is the range of this function: f(x)= 2x^2 - 1?

Answer 1

This is a parabola with min value = -1
So range is [-1, infinity}

Answer 2

Since x^2 is always going to be non-negative, that means the lowest it can be is 0. It can be as large as you want it. So the range goes from 2(0)-1 = 1, and doesn't have an end. You could write this as [1,∞)

Answer 3

the answer is [ -1, infinty)

since the parabola has a shift down to -1 ...is starts there nothing else matters