# Rearrangement Inequality

I recently read about the Rearrangement Inequality on AOPS , and understood most of it.

If we have two series ( say A & B ) of equal length , then the maximum value of the sum of product of their elements taken two at a time (one from each and not repeated ) is when the numbers to be multiplied are taken from sorted sets and with i=j.

It is easy to see that if there are N sets then we can easily find the maximum value of the sum of product of their elements taken N at a time (one from each and not repeated ) .

I am curious to know is there any general way to find the minimum value ?? All suggestions are welcome and please don't be shy to comment ...

Note by Sanjay Banerji
4 years, 5 months ago

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I'm curious what makes you so curious ...

- 4 years, 5 months ago

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