So let's start at zero, one, two, three, and then let's go to negative one. And we have a critical point at, let me do that in magenta. We have a critical point at x equals zero, right over there. And we have a critical point at x equals two, right over there. And so let's think about what g prime is doing in the intervals between the critical values or on either side of the critical values. So let's think about, let's first think about this interval. Let me do it in this purple color.