0:00
Hello.
00:01
So here, the volume of our solid is going to be given by the integral from negative 2 to 2.
00:06
And here we have that a of x is 4 times 4 minus x squared the x.
00:11
So we're going to get, well, a 2 times 4 come out front.
00:14
So we're going to have 8.
00:15
And then we integrate and we get 4x minus x cubed over 3, where we then evaluate from 0 to 2.
00:26
So that's going to give us 8 times 8 minus 8 thirds, which is going to give us that our volume is equal to 128 thirds.
00:42
All right.
00:43
And then for the next part here, well, the cross section now is a of x, which is going to be equal to square root of 4 times 2 times square root of 4 minus x squared all squared.
00:59
That gives us the square root of three times four minus x squared.
01:03
So the volume of our solid is going to be equal.
01:07
We can pull out a two root three.
01:09
So we have two times the square root of three and then times the integral from zero to two of four minus x squared, the x...