Mohammad K. Azarian,
“A Study of Risāla al-Watar wa’l Jaib” (The Treatise on the Chord and Sine): Revisited,
Forum Geometricorum, 18 (2018) 219--222.
Abstract. The purpose of this article is three-fold. First, we use Jamshīd al-Kāshī's cubic equation and Mathematica to calculate sin 1º to over 11,200,000 decimal digits of accuracy; an amazing improvement over the 17 digits of accuracy that al-Kāshī found by pencil and paper in 1426 . Then, we conjecture that al-Kāshī 's cubic equation can be used to calculate sin1º to any desired accuracy. Second, we set the record straight about the number of correct digits that al-Kāshī obtained. Third, we correct some statements that we made in .
Return to Forum Geom., 18 (2018) Table of Contents