00:01
Okay, so here we have our 3d space.
00:06
We have two equations, and we're going to find the intersection.
00:09
We have x or plus y squared equals four.
00:11
Let's make that four look a little bit bigger so we can read it.
00:15
So xr plus y squared equals four, and then we have z equals minus two.
00:21
So let's kind of look at what's going on here.
00:23
Okay, so xr plus y squared equals four means that z can be anything, but we get a circle of radius two.
00:33
So at z zero, we get a circle kind of like that.
00:35
It's radius two.
00:37
But z could be anything.
00:38
So basically, it's this long cylinder.
00:41
You can go all the way up and all the way down...