If and are positive real numbers satisfying , then the minimum possible value of is
If and are positive real numbers satisfying , then the minimum possible value of is
Entered answer:
Solution
We need to find the minimum value of given that .
Let us start by expanding the expression to better understand what we're working with.
Since , we can simplify :
So our expression becomes:
To minimize , we need to maximize (since gets smaller as gets larger).
The AM-GM Inequality states: For positive numbers and ,
This means:
Therefore:
The maximum value of is , and this happens when (equality in AM-GM occurs when the numbers are equal).
When :
Using the original form:
We used the fact that for a fixed sum, the product is maximized when the numbers are equal. This is a consequence of the AM-GM inequality, which is a powerful tool for optimization problems. The symmetry occurs because the optimal solution has .
Therefore, the minimum possible value is .
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