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Algebra Difficulty 5.0 AIME Find the answer

Let π\pi be a permutation of the numbers from 2 through 2012. Find the largest possible value of log2π(2)log3π(3)log2012π(2012)\log _{2} \pi(2) \cdot \log _{3} \pi(3) \cdots \log _{2012} \pi(2012).

A number or a short expression. Spacing and $ signs are ignored.

Solution

Note that i=22012logiπ(i)=i=22012logπ(i)logi=i=22012logπ(i)i=22012logi=1\begin{aligned} \prod_{i=2}^{2012} \log _{i} \pi(i) & =\prod_{i=2}^{2012} \frac{\log \pi(i)}{\log i} \\ & =\frac{\prod_{i=2}^{2012} \log \pi(i)}{\prod_{i=2}^{2012} \log i} \\ & =1 \end{aligned} where the last equality holds since π\pi is a permutation of the numbers 2 through 2012.

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