00:01
In this problem, we will cover local extrema.
00:03
So we know that we have a critical point at 0 -0, and we want to be able to classify what this point, what this critical point is.
00:13
And to do so, we must find the discriminant.
00:17
And we know that for this problem, we will be finding the second order partial derivatives.
00:25
To begin, we can see that the partial derivative with respect to x is going to be negative sign x, cost y, and the second partial derivative with respect to x is going to be negative cost x, cost y, and when we plug in the point zero zero, this will yield us a value of negative one.
01:00
Moving on, our partial derivative with respect to is going to be negative cos x, sine y, and the second partial derivative with respect to y is going to be negative cosy, or cos x, cosy...