Mathematician:Jamshīd al-Kāshī

Mathematician

Prominent mathematician of the newly-founded Samarkand Institute.

Best known for calculating the value of pi ($\pi$) to $16$ decimal places.

Nationality

Persian

History

• Born: c. 1380, Kashan, Iran
• Died: 22 June 1429, Samarkand, Transoxania

Theorems and Definitions

• The value of pi ($\pi$) to $16$ decimal places
• Law of Cosines (known in France as Théorème d'Al-Kashi (Al-Kashi's Theorem)
• Triple Angle Formula for Sine

Publications

• Khaqani Zij
• Sullam al-Sama
• The Treatise on the Chord and Sine
• The Key to Arithmetic in which Pascal's Triangle (under the name Khayyam's Triangle) is discussed

• 1416: Treatise on Astronomical Observational Instruments

Other inventions

• Plate of Conjunctions, an analog computing instrument used to determine the time of day at which planetary conjunctions will occur

• Plate of Zones, a mechanical planetary computer

Also known as

In Persian: محمد بن محمد بن الحسن طوسی -- Ghiyās-ud-dīn Jamshīd Kāshānī.

Sources

• John J. O'Connor and Edmund F. Robertson: "Jamshīd al-Kāshī": MacTutor History of Mathematics archive