Question: Under the Arab Empire, what subject was studied in the city where Husain al-Radi died?

full_context: Document 1: Mesopotamia: Mesopotamia is a historical region in West Asia situated within the Tigris -- Euphrates river system, in modern days roughly corresponding to most of Iraq plus Kuwait, the eastern parts of Syria, Southeastern Turkey, and regions along the Turkish -- Syrian and Iran -- Iraq borders.
Document 2: Hafizullah Amin: Hafizullah Amin (Pashto/Dari: حفيظ الله امين‎; born 1 August 1929 – 27 December 1979) was an Afghan communist politician during the Cold War. Amin was born in Paghman and educated at Kabul University, after which he started his career as a teacher. After a few years in that occupation, he went to the United States to study. He would visit the United States a second time before moving permanently to Afghanistan, and starting his career in radical politics. He ran as a candidate in the 1965 parliamentary election but failed to secure a seat. Amin was the only Khalqist elected to parliament in the 1969 parliamentary election, thus increasing his standing within the party. He was one of the leading organizers of the Saur Revolution which overthrew the government of Mohammad Daoud Khan. In 1979 he named himself president, prime minister, and chairman of the Khalq wing. He has been described as "ruthless" and a "radical Marxist".Amin's short-lived presidency was marked by controversies from beginning to end. He came to power by disposing of his predecessor Nur Muhammad Taraki and later ordering his death. Amin made attempts to win support from those who revolted against the communist regime which had begun under Taraki, but his government was unable to solve this problem. Many Afghans held Amin responsible for the regime's harshest measures, such as ordering thousands of executions. Thousands of people disappeared without trace during his time in office. The Soviet Union, which was dissatisfied with Amin, intervened in Afghanistan while invoking the Twenty-Year Treaty of Friendship between Afghanistan and the Soviet Union. Amin was assassinated by the Soviets on December 27, 1979 as part of Operation Storm-333, having ruled for slightly longer than three months.
Document 3: Muslim world: The Islamic Golden Age coincided with the Middle Ages in the Muslim world, starting with the rise of Islam and establishment of the first Islamic state in 622. The end of the age is variously given as 1258 with the Mongolian Sack of Baghdad, or 1492 with the completion of the Christian Reconquista of the Emirate of Granada in Al-Andalus, Iberian Peninsula. During the reign of the Abbasid caliph Harun ar-Rashid (786 to 809), the legendary House of Wisdom was inaugurated in Baghdad where scholars from various parts of the world sought to translate and gather all the known world's knowledge into Arabic. The Abbasids were influenced by the Quranic injunctions and hadiths, such as "the ink of a scholar is more holy than the blood of a martyr," that stressed the value of knowledge. The major Islamic capital cities of Baghdad, Cairo, and Córdoba became the main intellectual centers for science, philosophy, medicine, and education. During this period, the Muslim world was a collection of cultures; they drew together and advanced the knowledge gained from the ancient Greek, Roman, Persian, Chinese, Indian, Egyptian, and Phoenician civilizations.
Document 4: Madrasa: From around 750, during the Abbasid Caliphate, women “became renowned for their brains as well as their beauty”. In particular, many well known women of the time were trained from childhood in music, dancing and poetry. Mahbuba was one of these. Another feminine figure to be remembered for her achievements was Tawaddud, "a slave girl who was said to have been bought at great cost by Hārūn al-Rashīd because she had passed her examinations by the most eminent scholars in astronomy, medicine, law, philosophy, music, history, Arabic grammar, literature, theology and chess". Moreover, among the most prominent feminine figures was Shuhda who was known as "the Scholar" or "the Pride of Women" during the 12th century in Baghdad. Despite the recognition of women's aptitudes during the Abbasid dynasty, all these came to an end in Iraq with the sack of Baghdad in 1258.
Document 5: History of science: From their beginnings in Sumer (now Iraq) around 3500 BC, the Mesopotamian people began to attempt to record some observations of the world with numerical data. But their observations and measurements were seemingly taken for purposes other than for elucidating scientific laws. A concrete instance of Pythagoras' law was recorded, as early as the 18th century BC: the Mesopotamian cuneiform tablet Plimpton 322 records a number of Pythagorean triplets (3,4,5) (5,12,13). ..., dated 1900 BC, possibly millennia before Pythagoras,  but an abstract formulation of the Pythagorean theorem was not.
Document 6: Hilal Al-Ahmadi: Hilal Al-Ahmadi (1954? – 17 February 2011), who was an Iraqi veteran journalist with over 30 years of experience and well known for his reports about corruption, was assassinated in front of his home east of Mosul, Iraq.
Document 7: Ancient Near East: The ancient Near East was the home of early civilizations within a region roughly corresponding to the modern Middle East: Mesopotamia (modern Iraq, southeast Turkey, southwest Iran, northeastern Syria and Kuwait), ancient Egypt, ancient Iran (Elam, Media, Parthia and Persia), Anatolia / Asia Minor and Armenian Highlands (Turkey's Eastern Anatolia Region, Armenia, northwestern Iran, southern Georgia, and western Azerbaijan), the Levant (modern Syria, Lebanon, Palestine, Israel, and Jordan), Cyprus and the Arabian Peninsula. The ancient Near East is studied in the fields of Near Eastern archaeology and ancient history.
Document 8: Ismail Ahmed Rajab Al Hadidi: Ismail Ahmed Rajab Al Hadidi, the Arabic deputy for the Kurdish mayor-governor of city of Kirkuk in Iraq. Al Hadid was born in 1955, was elected as deputy for the mayor of Kirkuk, Abdul Rahman Mustafa in 2003 by the multiethnic city council of Kirkuk, after a Coalition Provisional Authority's organized election for a local city council in Kirkuk in May 2003, in Post-Saddam Hussein Iraq. Al Hadidi was wounded in the leg in an assassination bid in November 2003.
Document 9: History of science: In mathematics, the Persian mathematician Muhammad ibn Musa al-Khwarizmi gave his name to the concept of the algorithm, while the term algebra is derived from al-jabr, the beginning of the title of one of his publications. What is now known as Arabic numerals originally came from India, but Muslim mathematicians did make several refinements to the number system, such as the introduction of decimal point notation. Sabian mathematician Al-Battani (850-929) contributed to astronomy and mathematics, while Persian scholar Al-Razi contributed to chemistry and medicine.
Document 10: Islamism: While Qutb's ideas became increasingly radical during his imprisonment prior to his execution in 1966, the leadership of the Brotherhood, led by Hasan al-Hudaybi, remained moderate and interested in political negotiation and activism. Fringe or splinter movements inspired by the final writings of Qutb in the mid-1960s (particularly the manifesto Milestones, a.k.a. Ma'alim fi-l-Tariq) did, however, develop and they pursued a more radical direction. By the 1970s, the Brotherhood had renounced violence as a means of achieving its goals.
Document 11: History of science: In Babylonian astronomy, records of the motions of the stars, planets, and the moon are left on thousands of clay tablets created by scribes. Even today, astronomical periods identified by Mesopotamian proto-scientists are still widely used in Western calendars such as the solar year and the lunar month. Using these data they developed arithmetical methods to compute the changing length of daylight in the course of the year and to predict the appearances and disappearances of the Moon and planets and eclipses of the Sun and Moon. Only a few astronomers' names are known, such as that of Kidinnu, a Chaldean astronomer and mathematician. Kiddinu's value for the solar year is in use for today's calendars. Babylonian astronomy was "the first and highly successful attempt at giving a refined mathematical description of astronomical phenomena." According to the historian A. Aaboe, "all subsequent varieties of scientific astronomy, in the Hellenistic world, in India, in Islam, and in the West—if not indeed all subsequent endeavour in the exact sciences—depend upon Babylonian astronomy in decisive and fundamental ways."
Document 12: Abdul Fattah Ismail: He served as Chairman of the Presidium of the Supreme People's Council (head of state) and founder, chief ideologue, and first leader of the Yemeni Socialist Party from 21 December 1978 to 21 April 1980. He was summarily executed on 13 January 1986 along with three others, allegedly for "plotting to overthrow" Ali Nasir Muhammad's regime.
Document 13: Husain al-Radi: Husain Ar-Radi (1924, Najaf – 24 February 1963, Baghdad), also known as Hashiim, 'Ammar, and Salam Adil, was an Iraqi communist politician as well as a poet and painter. He was the leader of the Iraqi Communist Party from 1955 until his death by execution or under torture after the Baathist coup in 1963.
Document 14: History of mathematics: Babylonian mathematics refers to any mathematics of the peoples of Mesopotamia (modern Iraq) from the days of the early Sumerians through the Hellenistic period almost to the dawn of Christianity. The majority of Babylonian mathematical work comes from two widely separated periods: The first few hundred years of the second millennium BC (Old Babylonian period), and the last few centuries of the first millennium BC (Seleucid period). It is named Babylonian mathematics due to the central role of Babylon as a place of study. Later under the Arab Empire, Mesopotamia, especially Baghdad, once again became an important center of study for Islamic mathematics.
Document 15: Gamal Abdel Nasser: On 8 February 1963, a military coup in Iraq led by a Ba'athist–Nasserist alliance toppled Qasim, who was subsequently shot dead. Abdel Salam Aref, a Nasserist, was chosen to be the new president. A similar alliance toppled the Syrian government on 8 March. On 14 March, the new Iraqi and Syrian governments sent Nasser delegations to push for a new Arab union. At the meeting, Nasser lambasted the Ba'athists for "facilitating" Syria's split from the UAR, and asserted that he was the "leader of the Arabs". A transitional unity agreement stipulating a federal system was signed by the parties on 17 April and the new union was set to be established in May 1965. However, the agreement fell apart weeks later when Syria's Ba'athists purged Nasser's supporters from the officers corps. A failed counter-coup by a Nasserist colonel followed, after which Nasser condemned the Ba'athists as "fascists".
ground_truth: Islamic mathematics
sub_queries: Husain al-Radi >> place of death Answer: Baghdad
What subject was studied in Baghdad ? Answer: Islamic mathematics