Originally Posted by
qwertysaur
r and R are the radii of the circles on the top and bottom of the figure. h is the height of the figure.
V = π(r<sup>2</sup> +r*R + R<sup>2</sup>)h/3
Also this shape is called a Frustum.
I think you can derive that from calculus, yes, but it been years since I've done that
Interestingly, that formula also works for a normal cone as well, because it's just a special case frustum with one circle with radius 0 - substituting one of the radii with 0 wil give you the well-known formula for the volume of a cone