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National Olympiad First Round
2002 National Olympiad First Round
11
P11 [Combinatorics] - Turkish NMO 1st Round - 2002
P11 [Combinatorics] - Turkish NMO 1st Round - 2002
Source:
August 8, 2014
algebra
binomial theorem
Problem Statement
What is the coefficient of
x
5
x^5
x
5
in the expansion of
(
1
+
x
+
x
2
)
9
(1 + x + x^2)^9
(
1
+
x
+
x
2
)
9
?
<
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a
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1680
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882
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729
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450
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246
<span class='latex-bold'>a)</span>\ 1680 \qquad<span class='latex-bold'>b)</span>\ 882 \qquad<span class='latex-bold'>c)</span>\ 729 \qquad<span class='latex-bold'>d)</span>\ 450 \qquad<span class='latex-bold'>e)</span>\ 246
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1680
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>
882
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729
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450
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>
246
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