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Algebra Difficulty 6.8 National olympiad Find the answer

Find all triples of positive integers (x,y,z)(x,y,z) that satisfy the equation
\begin{align*} 2(x+y+z+2xyz)^2=(2xy+2yz+2zx+1)^2+2023 \end{align*}

A number or a short expression. Spacing and $ signs are ignored.

Solution

We claim that the only solutions are (2,3,3)(2,3,3) and its permutations.
Factoring the above squares and canceling the terms gives you:
8(xyz)2+2(x2+y2+z2)=4((xy)2+(yz)2+(zx)2)+20248(xyz)^2 + 2(x^2 +y^2 + z^2) = 4((xy)^2 + (yz)^2 + (zx)^2) + 2024
Jumping on the coefficients in front of the x2x^2 , y2y^2 , z2z^2 terms, we factor into:
(2x21)(2y21)(2z21)=2023(2x^2 - 1)(2y^2 - 1)(2z^2 - 1) = 2023
Realizing that the only factors of 2023 that could be expressed as (2x21)(2x^2 - 1) are 11 , 77 , and 1717 , we simply find that the only solutions are (2,3,3)(2,3,3) by inspection.
-Max
Alternatively, a more obvious factorization is:
2(x+y+z+2xyz)2=(2xy+2yz+2zx+1)2+20232(x+y+z+2xyz)^2=(2xy+2yz+2zx+1)^2+2023
(2x+2y+2z+22xyz)2(2xy+2yz+2zx+1)2=2023(\sqrt{2}x+\sqrt{2}y+\sqrt{2}z+2\sqrt{2}xyz)^2-(2xy+2yz+2zx+1)^2=2023
(22xyz+2xy+2yz+2zx+2x+2y+2z+1)(22xyz2xy2yz2zx+2x+2y+2z1)=2023(2\sqrt{2}xyz+2xy+2yz+2zx+\sqrt{2}x+\sqrt{2}y+\sqrt{2}z+1)(2\sqrt{2}xyz-2xy-2yz-2zx+\sqrt{2}x+\sqrt{2}y+\sqrt{2}z-1)=2023
(2x+1)(2y+1)(2z+1)(2x1)(2y1)(2z1)=2023(\sqrt{2}x+1)(\sqrt{2}y+1)(\sqrt{2}z+1)(\sqrt{2}x-1)(\sqrt{2}y-1)(\sqrt{2}z-1)=2023
(2x21)(2y21)(2z21)=2023(2x^2-1)(2y^2-1)(2z^2-1)=2023
Proceed as above. ~eevee9406

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Source: Omni-MATH, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.