# Abu Nasr Mansur

Abu Nasr Mansur | |
---|---|

Born |
970 Gīlān |

Died |
1036 Ghazni |

Fields | Astronomer Mathematician |

Known for | Trigonometry Law of sines |

Influences | Menelaus of Alexandria, Abu al-Wafa' |

Influenced | Al-Biruni |

**Abu Nasr Mansur ibn Ali ibn Iraq** (Persian: ابو نصر منصور بن علی بن عراق; c. 960 – 1036) was a Persian Muslim mathematician. He is well known for his work with the spherical sine law.^{[1]}^{[2]}

Abu Nasr Mansur was born in Gilan, Persia, to the ruling family of Khwarezm, the Afrighids.^{[3]} He was thus a prince within the political sphere. He was a student of Abu'l-Wafa and a teacher of and also an important colleague of the mathematician, Al-Biruni. Together, they were responsible for great discoveries in mathematics and dedicated many works to one another.

Most of Abu Nasr's work focused on math, but some of his writings were on astronomy. In mathematics, he had many important writings on trigonometry, which were developed from the writings of Ptolemy. He also preserved the writings of Menelaus of Alexandria and reworked many of the Greeks theorems.

He died in the Ghaznavid Empire (modern-day Afghanistan) near the city of Ghazna.

## References

- ↑
*Also the 'sine law' (of geometry and trigonometry, applicable to spherical trigonometry) is attributed, among others, to Alkhujandi. (The three others are Abul Wafa Bozjani, Nasiruddin Tusi and Abu Nasr Mansur).*Razvi, Syed Abbas Hasan (1991)*A history of science, technology, and culture in Central Asia, Volume 1*University of Peshawar, Peshawar, Pakistan, page 358, OCLC 26317600 - ↑ Bijli suggests that three mathematicians are in contention for the honor, Alkhujandi, Abdul-Wafa and Mansur, leaving out Nasiruddin Tusi. Bijli, Shah Muhammad and Delli, Idarah-i Adabiyāt-i (2004)
*Early Muslims and their contribution to science: ninth to fourteenth century*Idarah-i Adabiyat-i Delli, Delhi, India, page 44, OCLC 66527483 - ↑ Bosworth, C. E. "ĀL-E AFRĪḠ".
*Encyclopædia Iranica*. Columbia University. Retrieved 17 January 2013.

## Sources

- Berggren, J. Len (2007). "Ibn ʿIrāq: Abū Naṣr Manṣūr ibn ʿAlī ibn ʿIrāq". In Thomas Hockey; et al.
*The Biographical Encyclopedia of Astronomers*. New York: Springer. pp. 557–558. ISBN 978-0-387-31022-0. (PDF version) - O'Connor, John J.; Robertson, Edmund F., "Abu Nasr Mansur ibn Ali ibn Iraq",
*MacTutor History of Mathematics archive*, University of St Andrews. - SamsÓ, Julio (2008) [1970-80]. "Manṣūr Ibn 'Alī Ibn 'Irāq, Abū Naṣr".
*Complete Dictionary of Scientific Biography*. Encyclopedia.com.