00:01
We want to draw a contour map of f of xy is equal to x squared minus y with appropriate contour interval and showing at least six level curves.
00:14
So the first thing i'm going to do is go ahead and replace f of xy with c.
00:20
And then we can solve for y.
00:24
So we can add y over and then subtract c.
00:28
So we get y is equal to x squared minus c.
00:31
So now this will help us graph our contours a lot quicker, or our level curves a lot quicker.
00:40
So let's just go ahead and do the following.
00:43
So we can let c be in.
00:47
So let's do negative 2, negative 1, 0, 1, and 2, 1, and 2, and 2, and 3.
00:54
So 1, 2, 3, 4, 5, 6.
00:56
Yep, so that would be 6.
01:00
So when we have c is equal to zero, that would just give us the problem, x squared.
01:07
So that'll look something kind of like this here.
01:15
So something kind of like that.
01:20
And so this is when c is equal to zero, we get y is equal to x squared.
01:26
Now when c is equal to negative 1, we get x squared, minus 1, which would be x squared plus 1.
01:39
So it's going to look something kind of like this for that level curve.
01:47
And so this here is when c, actually let me go ahead and draw going up a little bit more on either side.
01:57
Just so i can draw above this.
02:00
So this is going to be c is equal to 1, or minus 1, i mean.
02:07
And so this is y is equal to x squared plus 1.
02:11
And then for when c is equal to negative 2, that would give us x squared plus 2...