And to think about this, I'm gonna make a number line. Let me find a nice, soothing color here. All right, that's a nice, soothing color. And let's say, I should make the number line a little bit bigger. So there we go. Let's utilize the screen space. And so if this is zero, this is negative one, this is negative two, this is positive one, this is positive two, we know that at x equals negative one and x equals one, our second derivative is equal to zero.