Cube of Sum Inequality

Show that $(x + y + z)^{3} > 27 x y z$ for positive real numbers $x, y, z$ .

~5 minProof · checked by AIAM-GM inequalityInequalities

H. S. Hall & S. R. Knight, Higher Algebra (1891) · Ch. XIX. Inequalities, Examples XIX.a, No. 17

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