f(x) = 1 / x^4
Notice that the unction is not defined at x = 0
But as x gets very close to 0 .......the numerator of the fraction is much greater than the denominator......and the range goes to infinity
As x moves out both ways from 0 to some large neg / pos x values....the denominator is much larger than the numerator........and the y value of the function approaches 0 in both directions
So....the range is (0, inf )