Glimpses in the History of a Great Number: Pi in Arabic Mathematics by Moustafa Mawaldi

https://muslimheritage.com/pi-in-arabic-mathematics/ The Greek letter pi (symbolized by π) is defined as the ratio of the circumference of the circle to its diameter. It is considered to be a vital element in the calculations of the area and sizes of several mathematical figures: the circle, the cube, the cone and the sphere, from which infinite practical applications have sprung. As a result, mathematicians in many civilizations: Greek, Chinese, Indian, Arabian and European have been highly concerned with calculating π as carefully as possible. This article by Professor Mustapha Mawaldi, the Director of the Institute for the History of Arabic Science in Aleppo, sheds light on the contribution of mathematicians of the Islamic civilisation in refining the value of pi. The works surveyed are those of Al-Khwarizmi, Al-Kashi, Al-Biruni, Al-Quhi, and Al-Kashi.