MHB Finding Min Value of $\dfrac{|b|+|c|}{a}$ from Roots of Cubic Equations

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The discussion revolves around finding the minimum value of the expression \(\dfrac{|b|+|c|}{a}\) given specific cubic equations with roots \(\alpha, \beta, \gamma\). The initial assumption was that the answer might be \(\dfrac{3}{a}\), but this was corrected. The actual minimum value is determined to be \(3888^{\frac{1}{6}}\). The conversation highlights the complexity of deriving the correct answer from the roots of the cubic equations. Overall, the focus is on accurately solving the mathematical problem presented.
anemone
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If $\alpha,\,\beta,\,\gamma$ are the roots of the equation $x^3+ax+1=0$, where $a$ is a positive real number and $\dfrac{\alpha}{\beta},\,\dfrac{\beta}{\gamma},\,\dfrac{\gamma}{\alpha}$ be the roots of the equation $x^3+bx^2+cx-1=0$, find the minimum value of $\dfrac{|b|+|c|}{a}$.
 
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is the answer 3/a
anemone said:
If $\alpha,\,\beta,\,\gamma$ are the roots of the equation $x^3+ax+1=0$, where $a$ is a positive real number and $\dfrac{\alpha}{\beta},\,\dfrac{\beta}{\gamma},\,\dfrac{\gamma}{\alpha}$ be the roots of the equation $x^3+bx^2+cx-1=0$, find the minimum value of $\dfrac{|b|+|c|}{a}$.

Is the answer $3/a$
 
solakis said:
Is the answer $3/a$

Nope, sorry solakis!
 
is the answer a number?
 
Hi solakis and to all MHB members,

I am sorry that I still haven't gotten around to follow up all my unanswered challenges here in MHB! (Sadface) I promise that once I got my personal things straighten out a bit more, I will have more time for MHB then.

To answer to your query, solakis, the answer to this problem is $3888^{\tiny\dfrac{1}{6}}$.
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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