00:01
Okay, we're using spherical coordinates and calculating the hemisphere, volume of the hemisphere from 5 pi over 4 to pi over 2, technically, this part of the volume like that, okay? so, what we're going to do is theta is going to go all around 0 to 2 pi.
00:27
Phi is going to go from pi over 4 to pi over 2.
00:34
And rho is going to go from 0 to 3.
00:36
And then rho squared sine phi is our jacobian.
00:42
And now we're going to do d rho d phi and d theta.
00:50
Okay.
00:50
So the best way to do these is to separate them, which is d theta.
00:58
And then d rho, which is rho squared d rho.
01:02
And then the phi part, which is pi over 4 to pi over 2, sine phi d phi, okay? now, this one is 2 pi...