The radius of the sphere is
.
Assume,
\The radius of the cylinder is
.
The height of the cylinder is
.
Phythagoras theorem :
.
Figure:
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Observe the figure :
\

The volume of the cylinder is
.


Find the maximum volume :
\
Differentiate on each side with respect to
.

.


Find the maximum volume of the cylinder is
at
.




.
Substitute
in
.




.
The maximum volume of the cylinder is
.
The maximum volume of the cylinder is
.