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MathNet 2019-part-03 — 184 problems (EN–VI) Question 29

Math Olympiad Vault · MathNet 2019-part-03 — 184 problems (EN–VI)

Question 29

If $\alpha$, $\beta$, $\gamma$ are positive real numbers such that $\frac{1}{\alpha} + \frac{1}{\beta} + \frac{1}{\gamma} = 3$, prove that
$$
\frac{\alpha + \beta}{\alpha^2 + \alpha\beta + \beta^2} + \frac{\beta + \gamma}{\beta^2 + \beta\gamma + \gamma^2} + \frac{\gamma + \alpha}{\gamma^2 + \gamma\alpha + \alpha^2} \le 2 .
$$
When is equality valid?