Brahmagupta
Brahmagupta ( – ) was an Indian mathematician and astronomer. He is the author of two early works on mathematics and astronomy: the '' Brāhmasphuṭasiddhānta'' (BSS, "correctly established doctrine of Brahma", dated 628), a theoretical treatise, and the '' Khaṇḍakhādyaka'' ("edible bite", dated 665), a more practical text. Brahmagupta was the first to give rules for computing with '' zero''. The texts composed by Brahmagupta were in elliptic verse in Sanskrit, as was common practice in Indian mathematics. As no proofs are given, it is not known how Brahmagupta's results were derived. In 628 CE, Brahmagupta first described gravity as an attractive force, and used the term "gurutvākarṣaṇam (गुरुत्वाकर्षणम्)" in Sanskrit to describe it. Life and career Brahmagupta was born in 598 CE according to his own statement. He lived in ''Bhillamāla'' in Gurjaradesa (modern Bhinmal in Rajasthan, India) during the reign of the Chavda dynasty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] 

Brahmagupta's Formula
In Euclidean geometry, Brahmagupta's formula is used to find the area of any cyclic quadrilateral (one that can be inscribed in a circle) given the lengths of the sides; its generalized version (Bretschneider's formula) can be used with noncyclic quadrilateral. Heron's formula can be thought as a subcase of the Brahmagupta's formula. Formula Brahmagupta's formula gives the area of a cyclic quadrilateral whose sides have lengths , , , as : K=\sqrt where , the semiperimeter, is defined to be : s=\frac. This formula generalizes Heron's formula for the area of a triangle. A triangle may be regarded as a quadrilateral with one side of length zero. From this perspective, as approaches zero, a cyclic quadrilateral converges into a cyclic triangle (all triangles are cyclic), and Brahmagupta's formula simplifies to Heron's formula. If the semiperimeter is not used, Brahmagupta's formula is : K=\frac\sqrt. Another equivalent version is : K=\frac\cdot Proof Trigonometric p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] 

Indian Mathematics
Indian mathematics emerged in the Indian subcontinent from 1200 BCE until the end of the 18th century. In the classical period of Indian mathematics (400 CE to 1200 CE), important contributions were made by scholars like Aryabhata, Brahmagupta, Bhaskara II, and Varāhamihira. The decimal number system in use today: "The measure of the genius of Indian civilisation, to which we owe our modern (number) system, is all the greater in that it was the only one in all history to have achieved this triumph. Some cultures succeeded, earlier than the Indian, in discovering one or at best two of the characteristics of this intellectual feat. But none of them managed to bring together into a complete and coherent system the necessary and sufficient conditions for a numbersystem with the same potential as our own." was first recorded in Indian mathematics. Indian mathematicians made early contributions to the study of the concept of zero as a number,: "...our decimal system, which (by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] 

Brahmagupta's Interpolation Formula
Brahmagupta's interpolation formula is a secondorder polynomial interpolation formula developed by the Indian mathematician and astronomer Brahmagupta (598–668 CE) in the early 7th century CE. The Sanskrit couplet describing the formula can be found in the supplementary part of ''Khandakadyaka'' a work of Brahmagupta completed in 665 CE. The same couplet appears in Brahmagupta's earlier ''Dhyanagrahaadhikara'', which was probably written "near the beginning of the second quarter of the 7th century CE, if not earlier." Brahmagupta was the one of the first to describe and use an interpolation formula using secondorder differences. Brahmagupta's interpolation formula is equivalent to modernday secondorder Newton–Stirling interpolation formula. Mathematicians prior to Brahmagupta used a simple linear interpolation In mathematics, linear interpolation is a method of curve fitting using linear polynomials to construct new data points within the range of a discrete s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] 

Brahmagupta–Fibonacci Identity
In algebra, the Brahmagupta–Fibonacci identity expresses the product of two sums of two squares as a sum of two squares in two different ways. Hence the set of all sums of two squares is closed under multiplication. Specifically, the identity says :\begin \left(a^2 + b^2\right)\left(c^2 + d^2\right) & = \left(acbd\right)^2 + \left(ad+bc\right)^2 & & (1) \\ & = \left(ac+bd\right)^2 + \left(adbc\right)^2. & & (2) \end For example, :(1^2 + 4^2)(2^2 + 7^2) = 26^2 + 15^2 = 30^2 + 1^2. The identity is also known as the Diophantus identity, Daniel Shanks, Solved and unsolved problems in number theory, p.209, American Mathematical Society, Fourth edition 1993. as it was first proved by Diophantus of Alexandria. It is a special case of Euler's foursquare identity, and also of Lagrange's identity. Brahmagupta proved and used a more general identity (the Brahmagupta identity), equivalent to :\begin \left(a^2 + nb^2\right)\left(c^2 + nd^2\r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] 

Indian Astronomy
Astronomy has long history in Indian subcontinent stretching from prehistoric to modern times. Some of the earliest roots of Indian astronomy can be dated to the period of Indus Valley civilisation or earlier. Astronomy later developed as a discipline of Vedanga, or one of the "auxiliary disciplines" associated with the study of the Vedas,Sarma (2008), ''Astronomy in India'' dating 1500 BCE or older. The oldest known text is the '' Vedanga Jyotisha'', dated to 1400–1200 BCE (with the extant form possibly from 700 to 600 BCE). Indian astronomy was influenced by Greek astronomy beginning in the 4th century BCEHighlights of Astronomy, Volume 11B: As presented at the XXIIIrd General Assembly of the IAU, 1997. Johannes Andersen Springer, 31 January 1999 – Science – 616 pages. page 72/ref>Babylon to Voyager and Beyond: A History of Planetary Astronomy. David Leverington. Cambridge University Press, 29 May 2010 – Science – 568 pages. page 4/ref>The History and Practice of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] 

Brahmagupta's Identity
In algebra, Brahmagupta's identity says that, for given n, the product of two numbers of the form a^2+nb^2 is itself a number of that form. In other words, the set of such numbers is closed under multiplication. Specifically: :\begin \left(a^2 + nb^2\right)\left(c^2 + nd^2\right) & = \left(acnbd\right)^2 + n\left(ad+bc\right)^2 & & & (1) \\ & = \left(ac+nbd\right)^2 + n\left(adbc\right)^2, & & & (2) \end Both (1) and (2) can be verified by expanding each side of the equation. Also, (2) can be obtained from (1), or (1) from (2), by changing ''b'' to −''b''. This identity holds in both the ring of integers and the ring of rational numbers, and more generally in any commutative ring. History The identity is a generalization of the socalled Fibonacci identity (where ''n''=1) which is actually found in Diophantus' ''Arithmetica'' (III, 19). That identity was rediscovered by Brahmagupta (598–668), an Indian mathemat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] 

Brahmagupta's Theorem
In geometry, Brahmagupta's theorem states that if a cyclic quadrilateral is orthodiagonal (that is, has perpendicular diagonals), then the perpendicular to a side from the point of intersection of the diagonals always bisects the opposite side. It is named after the Indian mathematician Brahmagupta (598668). Coxeter, H. S. M.; Greitzer, S. L.: ''Geometry Revisited''. Washington, DC: Math. Assoc. Amer., p. 59, 1967 More specifically, let ''A'', ''B'', ''C'' and ''D'' be four points on a circle such that the lines ''AC'' and ''BD'' are perpendicular. Denote the intersection of ''AC'' and ''BD'' by ''M''. Drop the perpendicular from ''M'' to the line ''BC'', calling the intersection ''E''. Let ''F'' be the intersection of the line ''EM'' and the edge ''AD''. Then, the theorem states that ''F'' is the midpoint ''AD''. Proof We need to prove that ''AF'' = ''FD''. We will prove that both ''AF'' and ''FD'' are in fact equal to ''FM''. To prove that ''AF'' = ''FM'', first note that t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] 

Brāhmasphuṭasiddhānta
The ''Brāhmasphuṭasiddhānta'' ("Correctly Established Doctrine of Brahma", abbreviated BSS) is the main work of Brahmagupta, written c. 628. This text of mathematical astronomy contains significant mathematical content, including a good understanding of the role of zero, rules for manipulating both negative and positive numbers, a method for computing square roots, methods of solving linear and quadratic equations, and rules for summing series, Brahmagupta's identity, and Brahmagupta theorem. The book was written completely in verse and does not contain any kind of mathematical notation. Nevertheless, it contained the first clear description of the quadratic formula (the solution of the quadratic equation).Bradley, Michael. ''The Birth of Mathematics: Ancient Times to 1300'', p. 86 (Infobase Publishing 2006). Positive and negative numbers ''Brāhmasphuṭasiddhānta'' is one of the first books to provide concrete ideas on positive numbers, negative numbers, and zero.Hen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] 

Brahmagupta's Problem
This problem was given in India by the mathematician Brahmagupta in 628 AD in his treatise '' Brahma Sputa Siddhanta'': Solve the Pell's equation : x^2  92y^2 = 1 for integers x,y>0. Brahmagupta gave the smallest solution as : (x,y) = (1151,120). See also *Brahmagupta *Indian mathematics * List of Indian mathematicians *Pell's equation *Indeterminate equation *Diophantine equation In mathematics, a Diophantine equation is an equation, typically a polynomial equation in two or more unknowns with integer coefficients, such that the only solutions of interest are the integer ones. A linear Diophantine equation equates to a ... External links {{mathworld, title=Brahmagupta's Problem, urlname=BrahmaguptasProblem Brahmagupta Diophantine equations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] 

Number System
A number is a mathematical object used to count, measure, and label. The original examples are the natural numbers 1, 2, 3, 4, and so forth. Numbers can be represented in language with number words. More universally, individual numbers can be represented by symbols, called ''numerals''; for example, "5" is a numeral that represents the number five. As only a relatively small number of symbols can be memorized, basic numerals are commonly organized in a numeral system, which is an organized way to represent any number. The most common numeral system is the Hindu–Arabic numeral system, which allows for the representation of any number using a combination of ten fundamental numeric symbols, called digits. In addition to their use in counting and measuring, numerals are often used for labels (as with telephone numbers), for ordering (as with serial numbers), and for codes (as with ISBNs). In common usage, a ''numeral'' is not clearly distinguished from the ''number'' that it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] 

Zero
0 (zero) is a number representing an empty quantity. In placevalue notation such as the Hindu–Arabic numeral system, 0 also serves as a placeholder numerical digit, which works by Multiplication, multiplying digits to the left of 0 by the radix, usually by 10. As a number, 0 fulfills a central role in mathematics as the additive identity of the integers, real numbers, and other algebraic structures. Common names for the number 0 in English are ''zero'', ''nought'', ''naught'' (), ''nil''. In contexts where at least one adjacent digit distinguishes it from the O, letter O, the number is sometimes pronounced as ''oh'' or ''o'' (). Informal or slang terms for 0 include ''zilch'' and ''zip''. Historically, ''ought'', ''aught'' (), and ''cipher'', have also been used. Etymology The word ''zero'' came into the English language via French from the Italian language, Italian , a contraction of the Venetian form of Italian via ''ṣafira'' or ''ṣifr''. In preIslamic time t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] 

Gurjaradesa
Gurjaradesa ("Gurjara country") or Gurjaratra is a historical region in India comprising the eastern Rajasthan and northern Gujarat during the period of 6th 12th century CE. The predominant power of the region, the GurjaraPratiharas eventually controlled a major part of North India centered at Kannauj. The modern state of "Gujarat" derives its name from the ancient Gurjaratra. Early references to Gurjara country ''Gurjaradēśa'', or Gurjara country, is first attested in Bana's ''Harshacharita'' (7th century CE). Its king is said to have been subdued by Harsha's father Prabhakaravardhana (died c. 605 CE). The bracketing of the country with Sindha (Sindh), Lāta (southern Gujarat) and Malava (western Malwa) indicates that the region including the northern Gujarat and Rajasthan is meant. Hieun Tsang, the Chinese Buddhist pilgrim who visited India between 631645 CE during Harsha's reign, mentioned the Gurjara country (''Kiuchelo'') with its capital at Bhinmal (''P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] 