MHB What Are the Positive Real Solutions for a and b in this Equation?

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The equation \( a + b + \frac{1}{a} + \frac{1}{b} + 4 = 2(\sqrt{2a+1} + \sqrt{2b+1}) \) requires finding all positive real solutions for \( a \) and \( b \). The discussion emphasizes the need to manipulate the equation to isolate terms involving \( a \) and \( b \). Participants suggest using substitutions or transformations to simplify the problem. The exploration includes analyzing the behavior of the equation under various conditions to identify potential solutions. Ultimately, the goal is to derive specific values or relationships between \( a \) and \( b \) that satisfy the equation.
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Determine all positive real $a$ and $b$ satisfying the equation $a+b+\dfrac{1}{a}+\dfrac{1}{b}+4=2(\sqrt{2a+1}+\sqrt{2b+1})$.
 
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Solution of other:

Notice that $a+\dfrac{1}{a}+2-2\sqrt{2a+1}=\dfrac{a^2+2a+1-2a\sqrt{2a+1}}{a}=\dfrac{(a-\sqrt{2a+1})^2}{a}$ .

Hence the original equation can be rewritten as

$\dfrac{(a-\sqrt{2a+1})^2}{a}+\dfrac{(b-\sqrt{2b+1})^2}{b}=0$.

For $a,\,b>0$, this gives $a-\sqrt{2a+1}=0$ and $b-\sqrt{2b+1}=0$. It follows that the only solution is $a=b=1+\sqrt{2}$.
 
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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