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Problems
Contests
National and Regional Contests
Turkey Contests
National Olympiad First Round
1999 National Olympiad First Round
36
36
Part of
1999 National Olympiad First Round
Problems
(1)
Trigonometric Inequality
Source: 0
4/21/2009
Let
x
1
,
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2
,
…
,
x
9
x_{1} ,x_{2} ,\ldots ,x_{9}
x
1
,
x
2
,
…
,
x
9
be real numbers on \left[ \minus{} 1,1\right]. If \sum _{i \equal{} 1}^{9}x_{i}^{3} \equal{} 0, then what is the largest possible value of \sum _{i \equal{} 1}^{9}x_{i}?
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1
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9
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None
<span class='latex-bold'>(A)</span>\ 1 \qquad<span class='latex-bold'>(B)</span>\ \frac {3}{2} \qquad<span class='latex-bold'>(C)</span>\ 3 \qquad<span class='latex-bold'>(D)</span>\ \frac {9}{2} \qquad<span class='latex-bold'>(E)</span>\ \text{None}
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2
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None
inequalities
trigonometry