2. Fibonacci (c. 1175 – c. 1250) was an Italian mathematician from the Republic of Pisa, considered to be "the
most talented Western mathematician of the Middle Ages". The name he is commonly called, "Fibonacci"
(Italian: [fiboˈnattʃi), was made up in 1838 by the French historian Guillaume Libri and is short for "filius
Bonacci" ("son of (the) Bonacci") and he is also known as Leonardo Bonacci, Leonardo of Pisa, Leonardo
Pisano Bigollo, or Leonardo Fibonacci.
Fibonacci popularized the Hindu–Arabic numeral system in the Western World primarily through his
composition in 1202 of Liber Abaci (Book of Calculation). He also introduced Europe to the sequence of
Fibonacci numbers, which he used as an example in Liber Abaci.
Biography
3. Fibonacci was born around 1175 to Guglielmo, a wealthy Italian merchant and, by some accounts,
the consul for Pisa. Guglielmo directed a trading post in Bugia, a port in the Almohad dynasty's
sultanate in North Africa. Fibonacci travelled with him as a young boy, and it was in Bugia (now
Béjaïa, Algeria) that he learned about the Hindu–Arabic numeral system.
Fibonacci travelled extensively around the Mediterranean coast, meeting with many merchants
and learning about their systems of doing arithmetic. He soon realised the many advantages of
the Hindu-Arabic system. In 1202, he completed the Liber Abaci (Book of Abacus or Book of
Calculation) which popularized Hindu–Arabic numerals in Europe.
Fibonacci became a guest of Emperor Frederick II, who enjoyed mathematics and science. In 1240,
the Republic of Pisa honored Fibonacci (referred to as Leonardo Bigollo) by granting him a salary
in a decree that recognized him for the services that he had given to the city as an advisor on
matters of accounting and instruction to citizens.
The date of Fibonacci's death is not known, but it has been estimated to be between 1240and 1250,
most likely in Pisa.
History
4. In the Liber Abaci (1202), Fibonacci introduced the so-called modus Indorum (method of the
Indians), today known as the Hindu–Arabic numeral system. The book advocated numeration
with the digits 0–9 and place value. The book showed the practical use and value of the new
Hindu-Arabic numeral system by applying the numerals to commercial bookkeeping, converting
weights and measures, calculation of interest, money-changing, and other applications. The book
was well-received throughout educated Europe and had a profound impact on European
thought. No copies of the 1202 edition are known to exist.
The 1228 edition, first section introduces the Hindu-Arabic numeral system and compares the
system with other systems, such as Roman numerals, and methods to convert the other numeral
systems into Hindu-Arabic numerals. Replacing the Roman numeral system, its ancient Egyptian
multiplication method, and using an abacus for calculations, with a Hindu-Arabic numeral
system was an advance in making business calculations easier and faster, which led to the growth
of banking and accounting in Europe.
The second section explains the uses of Hindu-Arabic numerals in business, for example
converting different currencies, and calculating profit and interest, which were important to the
growing banking industry. The book also discusses irrational numbers and prime numbers.
Liber Abaci
6.
Liber Abaci (1202), a book on calculations
Practica Geometriae (1220), a compendium of techniques in surveying,
the measurement and partition of areas and volumes, and other topics
in practical geometry
Flos (1225), solutions to problems posed by Johannes of Palermo
Liber quadratorum ("The Book of Squares") on Diophantine equations,
dedicated to Emperor Frederick II. See in particular congruum and the
Brahmagupta–Fibonacci identity.
Di minor guisa (on commercial arithmetic
Commentary on Book X of Euclid's Elements
Works
