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1976 IMO Longlists
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Part of
1976 IMO Longlists
Problems
(1)
5 lines for Turkevici's Inequality
Source: using classical inequality
11/15/2008
Let
a
,
b
,
c
,
d
a,b,c,d
a
,
b
,
c
,
d
be nonnegative real numbers. Prove that a^4\plus{}b^4\plus{}c^4\plus{}d^4\plus{}2abcd \ge a^2b^2\plus{}a^2c^2\plus{}a^2d^2\plus{}b^2c^2\plus{}b^2d^2\plus{}c^2d^2.
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