Re: integration

On Sat, 18 Feb 2006 16:58:11 -0000, "unknownking321"
<unknownking321@xxxxxxxxxxxxx> wrote:

The arc of the parabola with equation y² = 4ax, where a is a positive
constant, from the origin O to A (a, 2a) is rotated through 2? radians about
the x axis.

How do I show that the are of the surface generated is:

8?a² (2?2-1) / 3

Assuming "?" means perhaps "Pi" .... if you want "help", it means help
on what you have done to see if you are on the right track. What have
you done?

.