Let be the sides of the square ends and
be the length of the package.
Total area of the solid .
Find in terms of
.
Volume of the two hemispheres = Volume of one sphere.
\Formula for the volume of the sphere .
Formula for the volume of the cylinder .
Total volume of the solid .
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Solve for .
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Substitute in
.
.
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Differentiate on each side with respect to .
Find the critical numbers by equating derivative to zero.
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is minimum when
.
The radius of the cylinder that produces the minimum surface area is .
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