MHB Is Every Positive Real Number a Solution to (x+1)(x+2)(x+5)≥36x?

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The discussion centers on proving that every positive real number satisfies the inequality (x+1)(x+2)(x+5)≥36x. Participants analyze the inequality and explore various approaches to demonstrate its validity. The solution provided by castor28 is recognized as correct, contributing to the overall understanding of the problem. The conversation emphasizes the importance of mathematical proofs in validating inequalities. The thread highlights the collaborative effort in solving complex mathematical challenges.
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Here is this week's POTW:

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Prove that every positive real number satisfies $(x+1)(x+2)(x+5)\ge 36x$.

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Congratulations to castor28 for his correct solution (Cool) , which you can find below:
We have:
\begin{align*}
(x+1)(x+2)(x+5) - 36x &= x^3 + 8x^2 - 19x + 10\\
&= (x+10)(x-1)^2
\end{align*}
and this is non-negative for all positive $x$ (in fact, for all $x\ge-10$).