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.
 
Seemingly by some mathematical coincidence, a hexagon of sides 2,2,7,7, 11, and 11 can be inscribed in a circle of radius 7. The other day I saw a math problem on line, which they said came from a Polish Olympiad, where you compute the length x of the 3rd side which is the same as the radius, so that the sides of length 2,x, and 11 are inscribed on the arc of a semi-circle. The law of cosines applied twice gives the answer for x of exactly 7, but the arithmetic is so complex that the...

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