MHB How is $\sqrt{6}-\sqrt{2}$ equal to $2\sqrt{2-\sqrt{3}}$?

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The expression $\sqrt{6}-\sqrt{2}$ is not equal to $2\sqrt{2-\sqrt{3}}$. Numerical approximations show $\sqrt{6}-\sqrt{2} \approx 1.03528$ while $2\sqrt{2-\sqrt{3}}$ approximates to $1.09638$. The initial confusion arose from a misinterpretation of the notation, as the original post incorrectly referenced $2\sqrt{2-\sqrt{3}}$ instead of $2\sqrt{2}-\sqrt{3}$. The correct simplification shows that $\sqrt{6}-\sqrt{2}$ can be expressed as $\sqrt{2}(\sqrt{3}-1)$, leading to the conclusion that it can be rewritten in terms of $2\sqrt{2-\sqrt{3}}$. Therefore, the two expressions are not equivalent.
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how is $\sqrt{6}-\sqrt{2}$ equal to $2\sqrt{2-\sqrt{3}}$

please explain. Thanks!
 
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It does not. $\sqrt 6 - \sqrt 2 \approx 1.03528$, and $2 \sqrt 2 - \sqrt 3 \approx 1.09638$.
 
magneto said:
It does not. $\sqrt 6 - \sqrt 2 \approx 1.03528$, and $2 \sqrt 2 - \sqrt 3 \approx 1.09638$.

Notice OP wrote $2 \sqrt{2 - \sqrt{3}}$, not $2 \sqrt{2} - \sqrt{3}$.
 
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Then, $\sqrt 6 - \sqrt 2 = \sqrt 2 (\sqrt 3 - 1)$. Since the number are positive, use $a = \sqrt{a^2}$. $ \sqrt 2 (\sqrt 3 - 1) = \sqrt{2 (\sqrt{3}-1)^2}$, and deduce from there $2\sqrt{2-\sqrt 3}$.
 
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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