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MathNet 2022-part-04 — 197 problems (EN–VI) Question 179

Math Olympiad Vault · MathNet 2022-part-04 — 197 problems (EN–VI)

Question 179

Five positive reals $a$, $b$, $c$, $d$ and $e$ having product equal to $1$ are given. Prove that
$$
\frac{a^2}{b^2} + \frac{b^2}{c^2} + \frac{c^2}{d^2} + \frac{d^2}{e^2} + \frac{e^2}{a^2} \geq a + b + c + d + e.
$$