MHB Solving 8 Roots: Can 3 Quadratic Polynomials Fulfill $f(g(h(x)))=0$?

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The discussion explores the feasibility of constructing three quadratic polynomials, \( f(x) \), \( g(x) \), and \( h(x) \), to satisfy the equation \( f(g(h(x)))=0 \) with the roots being the integers 1 through 8. Participants analyze the implications of having eight distinct roots and the degree of the resulting polynomial composition. The challenge lies in the fact that each quadratic polynomial can contribute at most two roots, raising questions about the potential combinations and arrangements. Various mathematical strategies and approaches are considered to determine if such polynomials can exist. Ultimately, the consensus leans towards the conclusion that achieving eight distinct roots through this method is not possible.
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Is it possible to find three quadratic polynomials $f(x),\,g(x)$ and $h(x)$ such that the equation $f(g(h(x)))=0$ has the eight roots 1, 2, 3, 4, 5, 6, 7 and 8?
 
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Suppose there are such $f,\,g,\,h$. Then $h(1),\,h(2),\cdots,\,h(8)$ will be the roots of the 4th degree polynomial $f(g(x))$. Since $h(a)=h(b),\,a\ne b$ if and only if $a$ and $b$ are symmetric with respect to the axis of the parabola, it follows that $h(1)=h(8),\,h(2)=h(7),\,h(3)=h(6),\,h(4)=h(5)$ and the parabola $y=h(x)$ is symmetric with respect to $x=\dfrac{9}{2}$. Also, we have either $h(1)<h(2)<h(3)<h(4)$ or $h(1)>h(2)>h(3)>h(4)$.

Now, $g(h(1)),\,g(h(2)),\,g(h(3)),\,g(h(4))$ are the roots of the quadratic polynomial $f(x)$, so $g(h(1))=g(h(4))$ and $g(h(2))=g(h(3))$ , which implies $h(1)+h(4)=h(2)+h(3)$. For $h(x)=Ax^2+Bx+C$, this would force $A=0$, a contradiction.
 
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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