“牟合方盖”研究

Study on Mouhefanggai

我国很早就开始了球体积的研究 ,《九章算术》少广章得出的公式为V球 =9D3 / 1 6 ,三世纪数学家刘徽发现这是错误的 ,他认为球体积应为外切于它的一个牟合方盖的体积 ,所谓“牟合方盖”是两个半径相等的直交圆柱面相贯所围成的立体 .但刘徽没有直接求出牟合方盖的体积 .二百年后 ,祖冲之父子推得了 。

He considered that cubic measure is a three-dimensional folded by two intersecting cylinder outsidethrough each other.That is ,Mou He Fang Gai is cylinder outside equal its one cubic measure .However, Liu-Hui could not seek directly to cubic measure of Grind-in Square Canopy.After two hundred years,Zu and his son obtained the result.That is the Axiom by Zu Geng.