@article{oai:kindai.repo.nii.ac.jp:00007379, author = {来嶋, 大二}, issue = {48}, journal = {近畿大学工学部研究報告, Research reports of the Faculty of Engineering, Kinki University}, month = {Dec}, note = {[Abstract] A quadratic irrational is an irrational root of a quadratic polynomial with integer coefficients. Lagrange's theorem on continued fractions is as follows : any positive quadratic irrational has an eventually repeating continued fraction. A short proof of Lagrange's theorem is presented. Let D be a positive integer which is not a square, and p_i/q_i be the irreducible fraction of i-th convergent of √連分数とペル方程式 I}, year = {2014}, yomi = {キジマ, ダイジ} }