So it never goes to negative two sevenths. And the reason is is that this is not a differentiable function at x is equal to zero. It is not differentiable at x equals zero. Our slope jumps here. And because it's not differentiable, the mean value theorem doesn't apply. Now you can imagine if this was differentiable, if this did have a continuous derivative, then you would find a point. So if this looks something like this instead, I'll continue it over here.