朝鮮木版本『楊輝算法』の考察 : 高麗大学校木版本の発見をふまえて (The study of the history of mathematics 2016)

Abstract

The Yang Hui Suanfa (YHS) had a new direction of the mathematics in Eastern Asia, that is to say, speedy calculations for commercial trade, therefore it became the textbook in the Yi dynasty (1392-1910) in Korea. It was said that there were few sets of YHS in Korea, however the author found a Korean woodblock printing book at the Kogryo University in 2015. It has the same contents and mistakes as other Korean editions. We found the 8th set of YHS in the world, in the other words, the YHS was not so rear book in Korea, was quite popular for the mathematicians in Korea and Japan. Yang Hui studied higher degree equations quite deeply, he discovered that a quadratic equation has two solutions, that is to say, the new solving method of the "Fanjifa" in 1275. Although Jia Xian already discovered Jia Xian, Yang Hui and Pascal's triangle at the 11th century, but Yang Hui said it was "old" method for solving higher degree equations. Therefore I conclude that the "pre-modern age" would start from the 13th century, not the 16th century in Eastern Asia.