Thanks tiny Tim!
Yep.. You were right.
About Archimedes, I only find his ideas over a cylinder of the same radius as the sphere.
Anyway, thanks for you help
Homework Statement
Find the surface area of the surface x^2 + y^2 + z^2 = a^2 , that is outside the two cylinders x^2+y^2=\pm ax.
(a>0)
Homework Equations
ds= \sqrt{1+(Z_x')^2+(Z_y')^2}dxdy
The Attempt at a Solution
The intersections are clearly four ellipses. I will try to...