How to build a solid ...

Revolving Cube

Find the area between the curves ...

Find the area between the curves ...

Find the area between the curves ...

Find the area between the curves ...

Volume of a Cone

Any function rotated about the x-axis will have circular cross sections and it's volume can be found by:

In General:

A(x) is the function representing the changing areas

... so you need a function that represents r.

With circular cross sections