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 $3888^{\tiny\dfrac{1}{6}}$.
 
I have been insisting to my statistics students that for probabilities, the rule is the number of significant figures is the number of digits past the leading zeros or leading nines. For example to give 4 significant figures for a probability: 0.000001234 and 0.99999991234 are the correct number of decimal places. That way the complementary probability can also be given to the same significant figures ( 0.999998766 and 0.00000008766 respectively). More generally if you have a value that...

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