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Let R be the radius of a sphere and h the height of a spherical segment of one base, where 0 < h < 2R. The volume of the spherical segment is V, where
V/π = h2(R - h/3)The lateral surface area of the spherical segment is Sl, where
Sl/π = 2RhThe surface area of the base is Sb, where
Sb/π = r2and r is the radius of the base. The above three quantities are integers by convention. The base radius is related to the sphere radius and segment height by
r2 = R2 - |R - h|2,so
It follows that h2 is an integer and therefore![]()
is rational. Then![]()
is also rational. The fraction on the right is a quotient of two rational numbers, so 2h is rational and it follows that h is an integer.![]()
The equability requirement is
Since h < 2R, we have
![]()
[1]
so h = 5. It follows from [1] that R = 10/3. But then Sb/π = 25/3 is not an integer, so there are no equable spherical segments with integer volume and surface area sections.![]()
4 < h < 6,
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