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Orthogonal matrices with rational components in composing tests for High School students

Ruslan A. Sharipov
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Abstract

Fermat Last Theorem, which inspired mathematicians during 300 years, is proved by Andrew Wiles. Even among mathematicians there is a narrow circle of specialists, who can read this proof and understand all details. Is it a reason for pessimism? No, since arithmetics if entire numbers contains broad variety of problems with a simple statement, which might be not less intricate. One of them arises in elementary geometry.

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Ruslan A. Sharipov. 2000-06-30. Orthogonal matrices with rational components in composing tests for High School students. https://arxiv.org/abs/math/0006230

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