De quelques proprietes des nombres et des fractions decimales periodiques
by Étienne Midy
$4,500 · Offered by Sophia Rare Books
First edition
Nantes; Paris: the author & Forest; Bachelier, 1836. First edition, presentation copy, extremely rare, of the privately printed proof of Midy’s Theorem. “It is well known that a real number is rational if and only if its decimal expansion is a repeating decimal. For example, 2/7 = .285714285714 … Many students also know that if n/m is a rational number reduced to lowest terms
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