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Putnam
1970 Putnam
A5
A5
Part of
1970 Putnam
Problems
(1)
Putnam 1970 A5
Source: Putnam 1970
5/17/2022
Determine the radius of the largest circle which can lie on the ellipsoid
x
2
a
2
+
y
2
b
2
+
z
2
c
2
=
1
(
a
>
b
>
c
)
.
\frac{x^2 }{a^2 } +\frac{ y^2 }{b^2 } +\frac{z^2 }{c^2 }=1 \;\;\;\; (a>b>c).
a
2
x
2
+
b
2
y
2
+
c
2
z
2
=
1
(
a
>
b
>
c
)
.
Putnam
circle
ellipsoid