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happy.swan


Cho a, b, c >0. Chứng minh rằng:
$\frac{a^2}{b^3}+\frac{b^2}{c^3}+\frac{c^2}{a^3}$ \geq $\frac{1}{a}+\frac{1}{b}+\frac{1}{c}$.
$\frac{a^2}{b^3}+\frac{b^2}{c^3}+\frac{c^2}{a^3}$ \geq $\frac{1}{a}+\frac{1}{b}+\frac{1}{c}$.