Arithmetic mean and geometric mean

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The discussion centers on finding the minimum value of the expression [1/(1+ab)] + [1/(1+bc)] + [1+(1+ac)] given the constraint a² + b² + c² = 3 for positive real numbers a, b, and c. The established minimum value is 3/2, derived using the inequality A² + B² + C² ≥ AB + AC + BC. Participants emphasized the importance of showing work in homework-type questions to facilitate understanding.

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Homework Statement
Arithmetic mean and geometric mean
Relevant Equations
Arithmetic mean and geometric mean
If a, b, and c are positive real numbers and a² + b² + c² = 3, what is the minimum value of the expression [1/(1+ab)] + [1/(1+bc)] + [1+(1+ac )]?

Usage: A² + B² + C² ≥ AB+AC+BC

Answer: 3/2
 
Last edited:
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On any homework-type of question we are only allowed to give hints and guidance regarding the work that you show. You must show work on this problem.

PS. Your "Usage" statement for general A, B, C could be stronger.
 
Last edited:

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