Exercises. Determine whether each function is (a) strictly increasing, (b) non-decreasing, (c) strictly decreasing, (d) non-increasing, (e) none of the above. There may be more than one correct answer.
y = x<sup>2</sup>
The function y = x2 gets smaller on the interval (-∞, 0) and bigger on the interval (0,∞).
Over the whole real line, the function is (e) none of the above. Since it changes directions, this function is not strictly increasing, non-decreasing, strictly decreasing, or non-increasing.