Al-Khwarizmi

Muhammad ibn Musa al-Khwarizmi or better known as al-Khwarizmi was a very famous Persian polymath. He was born in 780 CE and died in 850 CE. Throughout his life, al-Khwarizmi produced a vast amount of influential works on mathematics, astronomy, and geography. Among his works, his treatise on algebra was the most distinguished one.
The term 'algebra' itself came from the word 'al-jabr' of al-Khwarizmi book's original title, "al-Kitāb al-Mukhtaṣar fī Ḥisāb al-Jabr wal-Muqābalah". 'Al-jabr' means 'completion' or 'rejoining'. This book is believed to be published around 813 - 833 CE. In this treatise on algebra, al-Khwarizmi introduced the first systematic solution of linear and quadratic equations. He successfully provided a demonstration on how to solve quadratic equations by completing the square, complete with its geometric justifications.
Al-Khwarizmi was the first person to introduce algebra as an independent discipline. He was also the one who initiate the methods of "reduction" and "balancing". Because of those achievements, he has been regarded as the Father of Algebra.
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