MHB Challenge Problem #7: Σ(x/(y^3+2))≥1

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The discussion revolves around proving the inequality Σ(x/(y^3+2))≥1 for positive real numbers x, y, and z such that xyz=1. Participants are encouraged to explore various mathematical approaches to demonstrate the validity of the inequality. The conversation highlights the importance of manipulating the terms and applying known inequalities to achieve the proof. A hint is provided to guide the participants in their reasoning. Engaging with this problem can deepen understanding of inequalities in mathematical analysis.
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Let $x,y,z$ be positive real numbers such that $xyz=1$. Prove that
$$\frac x{y^3+2}+\frac y{z^3+2}+\frac z{x^3+2}\ \geqslant\ 1.$$
 
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A hint ...

is requested (Giggle)
 
lfdahl said:
A hint ...

is requested (Giggle)
Niiiiice. (Clapping)

-Dan
 
Thread 'Erroneously  finding discrepancy in transpose rule'
Obviously, there is something elementary I am missing here. To form the transpose of a matrix, one exchanges rows and columns, so the transpose of a scalar, considered as (or isomorphic to) a one-entry matrix, should stay the same, including if the scalar is a complex number. On the other hand, in the isomorphism between the complex plane and the real plane, a complex number a+bi corresponds to a matrix in the real plane; taking the transpose we get which then corresponds to a-bi...

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