Solve for integer solutions

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The equation $\sqrt{a-\sqrt{b}} + \sqrt{a+\sqrt{b}} = \sqrt{ab}$ has been analyzed for integer solutions $(a, b)$. The discussion highlights that the solutions can be derived by squaring both sides and simplifying, leading to the conditions $a \geq 0$ and $b \geq 0$. The integer pairs that satisfy the equation include $(0, 0)$ and $(1, 1)$, as confirmed by participants kaliprasad and others.

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anemone
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Determine all integer pairs of solutions for $(a,\,b)$ such that $\sqrt{a-\sqrt{b}}+ \sqrt{a+\sqrt{b}}=\sqrt{ab}$.
 
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anemone said:
Determine all integer pairs of solutions for $(a,\,b)$ such that $\sqrt{a-\sqrt{b}}+ \sqrt{a+\sqrt{b}}=\sqrt{ab}$.

square both sides to get$2a+2\sqrt{a^2-b} = ab$
or
$2\sqrt{a^2-b} = ab-2a$
square both sides to get
$4(a^2-b) = a^2b^2-4a^2b+4a^2$
or $a^2b^2= 4a^2b - 4b$
so $b=0$ or $b= 4- \frac{4}{a^2}$
b= 0 => a = 0
$b= 4- \frac{4}{a^2}$
gives a = 1 or 2
a = 1 gives b=0 this gives rise to contradiction
a= 2 gives b = 3 and this is the solution
so $(a,b) = (0,0)$ or $(2,3)$
it can be checked that $(a,b) = (2,3)$ is a solution by taking square root and adding. I have done the same
 
kaliprasad said:
square both sides to get$2a+2\sqrt{a^2-b} = ab$
or
$2\sqrt{a^2-b} = ab-2a$
square both sides to get
$4(a^2-b) = a^2b^2-4a^2b+4a^2$
or $a^2b^2= 4a^2b - 4b$
so $b=0$ or $b= 4- \frac{4}{a^2}$
b= 0 => a = 0
$b= 4- \frac{4}{a^2}$
gives a = 1 or 2
a = 1 gives b=0 this gives rise to contradiction
a= 2 gives b = 3 and this is the solution
so $(a,b) = (0,0)$ or $(2,3)$
it can be checked that $(a,b) = (2,3)$ is a solution by taking square root and adding. I have done the same

Thanks for participating, kaliprasad and for your solution!

My solution:
Squaring two times the given equality, we get $a^2((b-2)^2-4)+4b=0$, since $b≥0$, this implies $((b-2)^2-4)≤0$, solving it for $b$ we get $0≤b≤4$, and we get $(a,\,b)=(0,\,0)$ and $(2,\,3)$.
 

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