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

AI Thread Summary
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.
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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 $3888^{\tiny\dfrac{1}{6}}$.
 
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