清代著名数学家董祐诚,继明安图之后研究“杜氏九术”,即三角函数的级数展开公式,他通过发现弦矢术和堆垛术之间的关系,利用中国传统数学历史悠久且成果卓著的堆垛求积术求解,方法独特,成就斐然,形成清代“九术”研究园地中的一朵奇葩。国内数学史界开始注意到他,但很少提及他的生平,对他主要著作中的思想方法 Dong Youcheng, a famous mathematician in the Qing Dynasty, studied the “Duji nine techniques” after Ming An Tu, which is the formula for the series expansion of trigonometric functions. He discovered the relationship between the string technique and the stacking technique and used traditional Chinese mathematics with a long history and The outstanding pile-stacked quadrature technique solves the problem with unique methods and brilliant achievements, forming a wonderful work in the research fields of the “Nine Techniques” in the Qing Dynasty. The world of mathematics began to notice him, but little mention was made of his life. His thoughts and methods in his major works