Thābit ibn Qurra
[5] Thābit was born in Harran in Upper Mesopotamia, which at the time was part of the Diyar Mudar subdivision of the al-Jazira region of the Abbasid Caliphate.
Thābit came to Baghdad in the first place to work for the Banū Mūsā becoming a part of their circle and helping them translate Greek mathematical texts.
[9] What is unknown is how Banū Mūsā and Thābit occupied himself with mathematics, astronomy, astrology, magic, mechanics, medicine, and philosophy.
[10] Thābit's native language was Syriac,[12] which was the Middle Aramaic variety from Edessa, and he was fluent in both Medieval Greek and Arabic.
[11] Thābit translated from Greek into Arabic works by Apollonius of Perga, Archimedes, Euclid and Ptolemy.
[citation needed] In regards to Ptolemy's Planetary Hypotheses, Thābit examined the problems of the motion of the Sun and Moon, and the theory of sundials.
[10] When looking at Ptolemy's Hypotheses, Thābit ibn Qurra found the Sidereal year which is when looking at the Earth and measuring it against the background of fixed stars, it will have a constant value.
[16] This was done while writing on the theory of numbers, extending their use to describe the ratios between geometrical quantities, a step which the Greeks did not take.
[17] He provided a strengthened extension[clarification needed] of Pythagoras' proof which included the knowledge of Euclid's fifth postulate.
[18] This postulate states that the intersection between two straight line segments combine to create two interior angles which are less than 180 degrees.
[19][clarification needed] The continued work done on geometric relations and the resulting exponential series allowed Thābit to calculate multiple solutions to chessboard problems.
His work with conic sections and the calculation of a paraboloid shape (cupola) show his proficiency as an Archimedean geometer.
This is further embossed[clarification needed] by Thābit's use of the Archimedean property in order to produce a rudimentary approximation of the volume of a paraboloid.
The use of uneven sections, while relatively simple, does show a critical understanding of both Euclidean and Archimedean geometry.
[25] Another piece of important text is Kitab fi sifat alwazn, which discussed concepts of equal-armed balance.
He also produced specific works on topics such as gallstones; the treatment of diseases such as smallpox, measles, and conditions of the eye; and discussed veterinary medicine and the anatomy of birds.
