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2012 China Northern MO
6
China Northern Mathematical Olympiad 2012 , Problem 6
China Northern Mathematical Olympiad 2012 , Problem 6
Source: China Taiyuan
October 3, 2014
function
logarithms
inequalities proposed
inequalities
Problem Statement
Prove that
(
1
+
1
3
)
(
1
+
1
3
2
)
⋯
(
1
+
1
3
n
)
<
2.
(1+\frac{1}{3})(1+\frac{1}{3^2})\cdots(1+\frac{1}{3^n})< 2.
(
1
+
3
1
)
(
1
+
3
2
1
)
⋯
(
1
+
3
n
1
)
<
2.
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