Hi All

I've come about another question which I'm curious about. This is how
it reads:-

A circular cylinder is cut out of a sphere with radius 10cm. Calculate
the maximum possible volume for the cylinder.

So I looked on the net for a solution and found the following page:-

http://library.thinkquest.org/C0110248/calculus/changemax.htm

 The only difference with the question on the above page and the one in
the book, is that the one in the above page specifies that the height
of the cylinder is 4x cm, while the one in the book does not. However,
the results on the above page agree with the answer in the text book,
so presumably the methods are valid.

What I couldn't figure out was why the height of the sphere should be
taken as 4x cm?

I would be most greatful for any advice.

Regards,

Paul