Possible Duplicate:
Why is the volume of a sphere $\frac{4}{3}\pi r^3$?
We know that the surface area of a sphere is $4\pi r^2$ and the volume is $\frac{4}{3}\pi r^3$, where $r$ is the radius of the sphere.
How does one prove these formulae?
Possible Duplicate:
Why is the volume of a sphere $\frac{4}{3}\pi r^3$?
We know that the surface area of a sphere is $4\pi r^2$ and the volume is $\frac{4}{3}\pi r^3$, where $r$ is the radius of the sphere.
How does one prove these formulae?