Bhaskara II Casey Gregory Background Information • • • • One of most famous Indian mathematicians Born 1114 AD in Bijjada Bida Father was a Brahman (Mahesvara) and astrologer Nicknamed Bhaskaracharya “Bhaskara the Teacher” • Studied Varahamihira and Brahmagupta at Uijain What he knew • Understood zero and negative numbers • Except how to divide by it • Knew x^2 had 2 solutions * • Had studied Pell’s equation and other Diophantine problems His Accomplishments • First to declare a/0 = * • First to declare + a = • Wrote 6 works including • • • • • • Lilavati (mathematics) Bijaganita (algebra) Siddhantasiromani Vasanabhasya (commentary on Siddhantasiromani) Karanakutuhala (astronomy) Vivarana Lilavati O girl! out of a group of swans, 7/2 times the square root of the number are playing on the shore of a tank. The two remaining ones are playing with amorous fight, in the water. What is the total number of swans? Lilavati 13 Chapters • definitions; arithmetical terms; interest; arithmetical and geometrical progressions; plane geometry; solid geometry; the shadow of the gnomon*; the kuttaka; combinations. • 2 Methods for multiplication* • 4 methods for squaring • Rules of three, five, seven and nine • Kuttaka Method • Example: “Say quickly, mathematician, what is that multiplier, by which two hundred and twenty-one being multiplied, and sixty-five added to the product, the sum divided by a hundred and ninety-five becomes exhausted.” • Bhaskaracharya is finding integer solution to 195x = 221y + 65. • He obtains the solutions (x,y) = (6,5) or (23,20) or (40, 35) and so on. Bijaganita • 12 Chapters • Including: positive and negative numbers; zero; the unknown; surds*; the kuttaka*; indeterminate quadratic equations; simple equations; quadratic equations; equations with more than one unknown; quadratic equations with more than one unknown; operations with products of several unknowns; and the author and his work • Quadratic equation - 700 A.D. Brahmagupta who also recognized 2 roots in the solution. 1100A.D. ANY positive number has 2 square roots • Tried to prove a/ 0 = , however if that were true, *0 = a, therefore proving all numbers equal • Shows that the kuttaka method to solve indeterminate equations such as ax + by + cz = d has more than one solution. • His conclusion shows his poetic and passionate nature: • “A morsel of tuition conveys knowledge to a comprehensive mind; and having reached it, expands of its own impulse, as oil poured upon water, as a secret entrusted to the vile, as alms bestowed upon the worthy, however little, so does knowledge infused into a wise mind spread by intrinsic force.” Siddhanta Siromani • Picture of Goladhyaya. Siddhanta Siromani • Wrote Siddhanta Siromani (1150 AD) • • • • Leelavati (arithmetic) Bijaganita (algebra) Goladhayaya (spheres, celestial globes) Grahaganita (mathematics of the planets) Topics Covered in Siddhanta Siromani • Astronomy Related • Latitudes & longitudes of the planets; three problems of diurnal* rotation; syzygies*; eclipses; the moon's crescent; conjunctions of the planets with each other and stars • Sphere Related • “nature of the sphere; cosmography and geography; planetary mean motion; eccentric epicyclic model of the planets; the armillary sphere; spherical trigonometry; ellipse calculations; first visibilities of the planets; calculating the lunar crescent; astronomical instruments; the seasons; and problems of astronomical calculations. Further Information in Siddhanta • First time trigonometry was studied as it’s own entity, rather than how it related to other calculations. • sin(a + b) = sin a cos b + cos a sin b • sin(a - b) = sin a cos b - cos a sin b. His 7th work? • There exists a 7th work, but it is thought to be a forgery. After Bhaskara II • Bhaskara II dies in 1185 • A HUGE scientific lull after invasion by muslims • 1727, next important Hindu mathematician Sawai Jai Singh II • Several of Bhaskara’s findings were not explored heavily after his death, and ended up being “discovered” later by European mathematicians. Bhaskara II Rediscovered • chakrawal, or the cyclic method, to solve algebraic equations. * • 6 centuries later, Galois, Euler and Lagrange rediscovered this and called it "inverse cyclic". • differential calculus • Rediscovered as "differential coefficient" • "Rolle's theorem" • Newton and Leibniz receive credit • Bhaskara is renowned for his concept of Tatkalikagati (instantaneous motion). Works Cited • http://www.ilovemaths.com/ind_mathe.htm • http://www.bbc.co.uk/dna/h2g2/A2982567 • http://www-groups.dcs.stand.ac.uk/%7Ehistory/Mathematicians/Bhas kara_II.html • http://www.math.sfu.ca/histmath/India/1 2thCenturyAD/Bhaskara.html