Irrationality of sum of roots of primes.

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SUMMARY

The discussion centers on the irrationality of the sum of square roots of prime numbers. The user establishes that $\sqrt{2}$, $\sqrt{2} + \sqrt{3}$, and $\sqrt{2} + \sqrt{3} + \sqrt{5}$ are irrational, leading to the conjecture that the sum $\sqrt{p_1} + \sqrt{p_2} + \sqrt{p_3} + \ldots + \sqrt{p_n}$ is irrational for all prime numbers $p_i$. However, the user notes that this approach does not extend to $n=4$, indicating a need for further exploration of the linear independence of square roots of primes over the rationals.

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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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