2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/32014Extending the classical Legendre's result, we describe all solutions of the inequality |x - a/b| < c/b^2 in terms of convergents of continued fraction expansion of x. Namely, we show that a/b = (rp_{m+1} +- sp_m) / (rq_{m+1} +- sq_m) for some nonnegative integers m,r,s such that rs < 2c. As an application of this result, we describe a modification of Verheul and van Tilborg variant of Wiener's attack on RSA cryptosystem with small secret exponent.11 pages, to appear in Tatra Mt. Math. PublCryptography and SecurityNumber TheoryE.3text