Abu Nasr Mansur ibn Ali ibn Iraq (c. 970 - 1036) was a Iraqi mathematician. He is well known for discovering the sine law. Events Major volcano eruption in Mashu Japan Devastating decade long famine begins in France Byzantine Emperor John I successfully defends the Eastern Roman Empire from massive barbarian invasion Construction completed on Al-Azhar mosque in Cairo, worlds oldest Islamic university Births Leif Ericson, Norse explorer Seyyed Razi, important Muslim... Events Emperor Go-Suzaku ascends the throne of Japan. ... Leonhard Euler is considered by many people to be one of the greatest mathematicians of all time A mathematician is a person whose primary area of study and research is mathematics. ... In trigonometry, the law of sines (or sine law) is a statement about arbitrary triangles in the plane. ...

Abu Nasr Mansur was born in Gilan to a ruling family of the region. He was thus a prince within the political sphere. He was a teacher of Al-Biruni and also an important colleague of the mathematician. Together they were responsible for great discoveries in mathematics and dedicated many works to one another. Guilan (گیلان in Persian) is one of the 30 provinces of Iran, during antique time known as part of Hyrcania, with a population of approximately 2 million and an area of 14,700 sq. ... Biruni commemorated on a Soviet stamp for his millennial anniversary. ...

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. Radio telescopes are among many different tools used by astronomers Astronomy (Greek: αστρονομία = άστρον + νόμος, astronomia = astron + nomos, literally, law of the stars) is the science of celestial objects and phenomena that originate outside the Earths atmosphere, such as stars, planets, comets, auroras, galaxies, and the cosmic background radiation. ... Wikibooks has more about this subject: Trigonometry Trigonometry (from the Greek trigonon = three angles and metro = measure) is a branch of mathematics dealing with angles, triangles and trigonometric functions such as sine, cosine and tangent. ... Claudius Ptolemaeus (Greek: ; c. ... Menelaus of Alexandria (born ca. ...

He died in modern-day Afghanistan near the city of Ghazna. This article incorporates text from the public domain 1911 Encyclopædia Britannica. ...

External link

• Mansur's Biography on St Andrew's School of Mathematics website, Scotland