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The square roots of the primes are linearly independent over the field of rationals
I am reading a research article in which there is a theorem regarding square roots of square free numbers. A number is square free if it is not divisible by square of any prime number. The theorem states the following:
$\text{The square roots of all positive square-free integers are linearly independent over }\mathbb{Q}.$
Unfortunately, it provides a reference to an article to which I don't have an access at the moment. The article is titled, "Linear Algebra Methods in Combinatorics."
I have tried few things, but I didn't go far with any of that. Can somebody provides me a starting point from where I can work things out myself? I don't want a full solution. Just a starting pointer is appreciated.