00:01
This question asked us to find the exact area of the surface obtained by rotating the curve about the x -axis.
00:05
As they stated, we're looking at between one -half and one, so those are our bounds, and then because we're rotating it, we know we need to add 2 -py.
00:13
Now, we know our original is x -cubed over 6 plus 1 over 2x.
00:18
This is the original expression we've been given.
00:20
We know this is also going to be multiplied by y -prime squared.
00:25
So 1 plus 1 4th, x to the 4th, minus 1 1⁄2x to the 4th.
00:33
And again, as i stated, this is the formula listed in the textbook, where you've got like 2 pi, and they've got y prime squared, so 2 pi r squared, or whatever the formula is, how you consider it to be...