MHB Does the equation $a^2=b^4+b^2+1$ have integer solutions?

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The equation \( a^2 = b^4 + b^2 + 1 \) has been discussed regarding its integer solutions. It has been established that the only integer solutions are \( (a, b) = (\pm 1, 0) \). The discussion acknowledges this valid solution but suggests rephrasing the problem to exclude it. Ultimately, the focus remains on the existence of integer solutions, confirming that only the specified pair qualifies. The equation does not have other integer solutions beyond this pair.
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Show that the equation $a^2=b^4+b^2+1$ does not have integer solutions.
 
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anemone said:
Show that the equation $a^2=b^4+b^2+1$ does not have integer solutions.
$a=\pm 1 ,\, and \,\, b=0 $ are two sets of integer solutions
 
Albert said:
$a=\pm 1 ,\, and \,\, b=0 $ are two sets of integer solutions

Oh...it was my bad that I didn't see $(a,\,b)=(\pm1,\,0)$ is the valid solution to this problem. Sorry!:o

Let me rephrase the original problem so that it does not have integer solutions, except for $(a,\,b)=(\pm1,\,0)$.
 
$a^2=b^4+b^2+1---(1)$
$\left | a \right |$ must be odd
let $a=2x+1,\,\, and, \,\, y=b^2\geq 0$
from (1) we have:
$4x^2+4x+1=y^2+y+1$
$\therefore 4x(x+1)=y(y+1)---(2)$
the only possible solutions for (2) will be :$4x(x+1)=y(y+1)=0$
we get $x=0 ,\,\, or,\,\, x=-1$
and the corresponding solutions of $a,\,\, and \,\,\, b $ will be :$a=\pm 1,\,\, and\,\, \, b=0$
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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