|
Abu Al-Wafa' Buzjani
Abū al-Wafāʾ, Muḥammad ibn Muḥammad ibn Yaḥyā ibn Ismāʿīl ibn al-ʿAbbās al-Būzjānī or Abū al-Wafā Būzhjānī ( fa, ابوالوفا بوزجانی or بوژگانی) (10 June 940 – 15 July 998) was a Persian mathematician and astronomer who worked in Baghdad. He made important innovations in spherical trigonometry, and his work on arithmetics for businessmen contains the first instance of using negative numbers in a medieval Islamic text. He is also credited with compiling the tables of sines and tangents at 15 ' intervals. He also introduced the secant and cosecant functions, as well studied the interrelations between the six trigonometric lines associated with an arc. His ''Almagest'' was widely read by medieval Arabic astronomers in the centuries after his death. He is known to have written several other books that have not survived. Life He was born in Buzhgan, (now Torbat-e Jam) in Khorasan (in today's Iran). At age 19, in 959 AD, he moved to Baghd ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buzhgan
Būzghān ( fa, بوژگان) (also Puchkan, Buzjan) is a village in Torbat-e-Jam County in Iran's Khorasan-e Razavi province. Historically Buzghan was a city and was the seat of government in the historic Persian province of Jam (Zam). Notable residents * Abu al-Wafa' Buzjani, one of the most important Persian astronomers and mathematicians * Abuzar Buzjani Abuzar Buzjani (also spelled ''Abudarr Buzjani'', in Persian:ابوذر بوزجانی - died 977 or 978) was a Persian poet and Sufi shaikh contemporary with Sebüktigin, the founder of the Ghaznavid Empire in ancient Iran. Abūzar was born an ..., Persian poet Populated places in Razavi Khorasan Province Nishapur Quarter {{RazaviKhorasan-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Negative Numbers
In mathematics, a negative number represents an opposite. In the real number system, a negative number is a number that is less than zero. Negative numbers are often used to represent the magnitude of a loss or deficiency. A debt that is owed may be thought of as a negative asset. If a quantity, such as the charge on an electron, may have either of two opposite senses, then one may choose to distinguish between those senses—perhaps arbitrarily—as ''positive'' and ''negative''. Negative numbers are used to describe values on a scale that goes below zero, such as the Celsius and Fahrenheit scales for temperature. The laws of arithmetic for negative numbers ensure that the common-sense idea of an opposite is reflected in arithmetic. For example, −(−3) = 3 because the opposite of an opposite is the original value. Negative numbers are usually written with a minus sign in front. For example, −3 represents a negative quantity with a magnitude of three, and is pronounced "minu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buyid
The Buyid dynasty ( fa, آل بویه, Āl-e Būya), also spelled Buwayhid ( ar, البويهية, Al-Buwayhiyyah), was a Shia Iranian dynasty of Daylamite origin, which mainly ruled over Iraq and central and southern Iran from 934 to 1062. Coupled with the rise of other Iranian dynasties in the region, the approximate century of Buyid rule represents the period in Iranian history sometimes called the 'Iranian Intermezzo' since, after the Muslim conquest of Persia, it was an interlude between the rule of the Abbasid Caliphate and the Seljuk Empire. The Buyid dynasty was founded by 'Ali ibn Buya, who in 934 conquered Fars and made Shiraz his capital. His younger brother Hasan ibn Buya conquered parts of Jibal in the late 930s, and by 943 managed to capture Ray, which he made his capital. In 945, the youngest brother, Ahmad ibn Buya, conquered Iraq and made Baghdad his capital. He received the ''laqab'' or honorific title of ''Mu'izz al-Dawla'' ("Fortifier of the State"). The e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambridge University Press
Cambridge University Press is the university press of the University of Cambridge. Granted letters patent by Henry VIII of England, King Henry VIII in 1534, it is the oldest university press A university press is an academic publishing house specializing in monographs and scholarly journals. Most are nonprofit organizations and an integral component of a large research university. They publish work that has been reviewed by schola ... in the world. It is also the King's Printer. Cambridge University Press is a department of the University of Cambridge and is both an academic and educational publisher. It became part of Cambridge University Press & Assessment, following a merger with Cambridge Assessment in 2021. With a global sales presence, publishing hubs, and offices in more than 40 Country, countries, it publishes over 50,000 titles by authors from over 100 countries. Its publishing includes more than 380 academic journals, monographs, reference works, school and uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kushyar Gilani
Abul-Hasan Kūshyār ibn Labbān ibn Bashahri Daylami (971–1029), also known as Kūshyār Daylami ( fa, کوشیار دیلمی), was an Iranian mathematician, geographer, and astronomer from Daylam, south of the Caspian Sea, Iran. Career His main work was probably done about the beginning of the eleventh century, and seems to have taken an important part in the elaboration of trigonometry. For example, he continued the investigations of Abul Wáfa, and devoted much space to this in his zij (or collection of tables) ''az-Zīj al-Jamī wal-Baligh'' ("the comprehensive and mature tables"), which incorporated the improved values of the planetary apogees observed by al-Battani.E. S. Kennedy, ''A Survey of Islamic Astronomical Tables,'' (Transactions of the American Philosophical Society, New Series, 46, 2), Philadelphia, 1956, pp. 3, 34-5. The tables were translated into Persian before the end of the century. He wrote also an astrological introduction and an arithmetic treatise ''Kit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abu-Mahmud Khojandi
Abu Mahmud Hamid ibn al-Khidr al-Khojandi (known as Abu Mahmood Khojandi, Alkhujandi or al-Khujandi, Persian: ابومحمود خجندی, c. 940 - 1000) was a Muslim Transoxanian astronomer and mathematician born in Khujand (now part of Tajikistan) who lived in the late 10th century and helped build an observatory, near the city of Ray (near today's Tehran), in Iran. Astronomy Khojandi worked under the patronage of the Buwayhid Amirs at the observatory near Ray, Iran, where he is known to have constructed the first huge mural sextant in 994 AD, intended to determine the Earth's axial tilt ("obliquity of the ecliptic") to high precision. He determined the axial tilt to be 23°32'19" for the year 994 AD. He noted that measurements by earlier astronomers had found higher values (Indians: 24°; Ptolemy 23° 51') and thus discovered that the axial tilt is not constant but is in fact (currently) decreasing. His measurement of the axial tilt was however about 2 minutes too small, prob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Al-Sijzi
Abu Sa'id Ahmed ibn Mohammed ibn Abd al-Jalil al-Sijzi (c. 945 - c. 1020, also known as al-Sinjari and al-Sijazi; fa, ابوسعید سجزی; Al-Sijzi is short for "Al-Sijistani") was an Iranian Muslim astronomer, mathematician, and astrologer. He is notable for his correspondence with al-Biruni and for proposing that the Earth rotates around its axis in the 10th century. He dedicated work to 'Adud al-Daula, who was probably his patron, and to the prince of Balkh. He also worked in Shiraz making astronomical observations from 969 to 970. Mathematics Al-Sijzi studied intersections of conic sections and circles. He replaced the old kinematical trisection of an angle by a purely geometric solution (intersection of a circle and an equilateral hyperbola.) Earth's rotation Al-Biruni tells us that Al-Sijzi invented an astrolabe, called "al-zūraqī", whose design was based on the idea that the Earth rotates: Al-Biruni also referred to Al-Sijzi as a prominent astronomer who d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abū Sahl Al-Qūhī
(; fa, ابوسهل بیژن کوهی ''Abusahl Bijan-e Koohi'') was a Persian mathematician, physicist and astronomer. He was from Kuh (or Quh), an area in Tabaristan, Amol, and flourished in Baghdad in the 10th century. He is considered one of the greatest geometers, with many mathematical and astronomical writings ascribed to him. Al-Qūhī was the leader of the astronomers working in 988 AD at the observatory built by the Buwayhid amir Sharaf al-Dawla in Badhdad. He wrote a treatise on the astrolabe in which he solves a number of difficult geometric problems. In mathematics he devoted his attention to those Archimedean and Apollonian problems leading to equations higher than the second degree. He solved some of them and discussed the conditions of solvability. For example, he was able to solve the problem of inscribing an equilateral pentagon into a square, resulting in a fourth degree equation. He also wrote a treatise on the "perfect compass", a compass with one leg o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greater Khorasan
Greater Khorāsān,Dabeersiaghi, Commentary on Safarnâma-e Nâsir Khusraw, 6th Ed. Tehran, Zavvâr: 1375 (Solar Hijri Calendar) 235–236 or Khorāsān ( pal, Xwarāsān; fa, خراسان ), is a historical eastern region in the Iranian Plateau between Western and Central Asia. The name ''Khorāsān'' is Persian and means "where the sun arrives from" or "the Eastern Province".Sykes, M. (1914). "Khorasan: The Eastern Province of Persia". ''Journal of the Royal Society of Arts'', 62(3196), 279-286.A compound of ''khwar'' (meaning "sun") and ''āsān'' (from ''āyān'', literally meaning "to come" or "coming" or "about to come"). Thus the name ''Khorasan'' (or ''Khorāyān'' ) means "sunrise", viz. " Orient, East"Humbach, Helmut, and Djelani Davari, "Nāmé Xorāsān", Johannes Gutenberg-Universität Mainz; Persian translation by Djelani Davari, published in Iranian Languages Studies Website. MacKenzie, D. (1971). ''A Concise Pahlavi Dictionary'' (p. 95). London: Oxford University ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torbat-e Jam
Torbat-e Jawm ( fa, تربت جام, Torbat-e Jām; also known as Torbat-e Sheykh Jām and Turbat-i-Shaikh Jam) is a city and capital of Torbat-e Jam County, in Razavi Khorasan Province, Iran. At the 2016 census, its population was 100,449. Torbat-e Jam is one of the ancient cities of Greater Khorasan. Torbat-e Jām is an ancient city with a Sunni-majority population. It is about southwest of Mashhad, about north of Taybad, and about west of the Afghanistan border. There are many ancient places there, like the ''mazar'' (tomb) of Sheikh Ahmad Jami and Prince Qasem-e Anvar. The county includes many villages, such as Bezd, Mahmoodabad, Nilshahr. Music Torbat-e-Jam music has a long history in Iranian culture. The dotar is the most important and common instrument among the people of Torbat-e-Jam, which is played with great skill. The music of this land originates from the heart of rituals and customs that are thousands of years old. Poetry reading, salawat reading, travel musi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trigonometry
Trigonometry () is a branch of mathematics that studies relationships between side lengths and angles of triangles. The field emerged in the Hellenistic world during the 3rd century BC from applications of geometry to astronomical studies. The Greeks focused on the calculation of chords, while mathematicians in India created the earliest-known tables of values for trigonometric ratios (also called trigonometric functions) such as sine. Throughout history, trigonometry has been applied in areas such as geodesy, surveying, celestial mechanics, and navigation. Trigonometry is known for its many identities. These trigonometric identities are commonly used for rewriting trigonometrical expressions with the aim to simplify an expression, to find a more useful form of an expression, or to solve an equation. History Sumerian astronomers studied angle measure, using a division of circles into 360 degrees. They, and later the Babylonians, studied the ratios of the sides of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trigonometric Functions
In mathematics, the trigonometric functions (also called circular functions, angle functions or goniometric functions) are real functions which relate an angle of a right-angled triangle to ratios of two side lengths. They are widely used in all sciences that are related to geometry, such as navigation, solid mechanics, celestial mechanics, geodesy, and many others. They are among the simplest periodic functions, and as such are also widely used for studying periodic phenomena through Fourier analysis. The trigonometric functions most widely used in modern mathematics are the sine, the cosine, and the tangent. Their reciprocals are respectively the cosecant, the secant, and the cotangent, which are less used. Each of these six trigonometric functions has a corresponding inverse function, and an analog among the hyperbolic functions. The oldest definitions of trigonometric functions, related to right-angle triangles, define them only for acute angles. To extend the sine and cos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
