MHB Irrationality of sum of roots of primes.

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The discussion explores the irrationality of sums of square roots of prime numbers, starting with established cases like $\sqrt{2}$ and $\sqrt{2} + \sqrt{3}$. It proposes that sums of the form $\sqrt{p_1} + \sqrt{p_2} + \sqrt{p_3} + \ldots + \sqrt{p_n}$ are irrational for all n, based on a method used for three primes. However, the method fails for four primes, prompting a request for alternative approaches. The conversation highlights the linear independence of square roots of primes over the rationals as a key point. Overall, the thread seeks to deepen understanding of the irrationality of sums involving prime roots.
caffeinemachine
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I observed the following:

1) $\sqrt{2}$ is irrational.

2) $\sqrt{2}+\sqrt{3}$ is irrational(since its square is irrational).

3) $\sqrt{2}+\sqrt{3}+\sqrt{5}$ is irrational(assume its rational and is equal to $r$. Write $r- \sqrt{5}=\sqrt{2} + \sqrt{3}$. Now square both the sides and its obvious from here).

So I am thinking may be $\sqrt{p_1} + \sqrt{p_2} + \sqrt{p_3} + \ldots + \sqrt{p_n}$ is irrational for all $n$, where $p_i$ is the $i-th$ prime.

The trick I used for (3) doesn't work for $n=4$. Any ideas anyone?
 
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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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