So let's see, if we take, so it's going to be x squared is going to be equal to, 256 is 16 squared, so this is 16, this is going to be x squared is equal to 16, or x is equal to 4. Now, that's our only critical point we have, so that's probably the x value that minimizes our sum of squares right over here, but let's make sure it's a minimum value, and to do that, we can just do our second derivative test. So let's figure out, let's take the second derivative, s prime prime of x, and figure out if we are concave upwards or downwards when x is equal to 4. So s prime prime of x is going to be equal to 2, and then we're going to have negative 3 times negative 512, so I'll just write that as plus 3 times 512, that's going to be 1536, is that right? Yeah, 3 times 500 is 1500, 3 times 12 is 36, x to the negative 4 power. So this thing is going to be, this thing right over here is actually going to be positive for any x, this thing is going to be positive for any x. x to the negative 4, even if it's a negative x value, that's going to be positive, everything else is positive, this thing is always positive. So we are always in a concave upwards situation.