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41. Cubic Equation
be called complex numbers, but a few years later rafael bombelli (15261672)gave several examples that involved these strange new mathematical beasts.
http://www.daviddarling.info/encyclopedia/C/cubic_equation.html
Return to The Worlds of David Darling
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cubic equation
A polynomial equation of the third degree, the general form of which is ax bx cx d where a b c , and d are constants. There was a great controversy in sixteenth-century Italy between Girolamo Cardano and Niccoló Tartaglia about who should get credit for solving the cubic. At this time symbolic algebra hadn't been developed, so all the equations were written in words instead of symbols. Early studies of cubics helped legitimize negative numbers , give a deeper insight into equations in general, and stimulate work that eventually led to the discovery and acceptance of complex numbers . Cardano, in his Ars magna , found negative solutions to equations, but called them "fictitious". He also noted an important fact connecting solutions of a cubic equation to its coefficients , namely, that the sum of the solutions is the negation of b , the coefficient of the x term. At one other point, he mentions that the problem of dividing 10 into two parts so that their product is 40 would have to be 5 +

42. Complex Numbers
the hydraulic engineer rafael bombelli (15261572) almost thirty years after bombelli justified the use of Cardan s formula by introducing complex
http://www.und.nodak.edu/instruct/lgeller/complex.html
Complex Numbers
The usual definition of complex numbers is all numbers of the form a+b i , where a and b are real numbers and i , the imaginary unit, is a number such that its square is -1. This gives no insight to where these came from nor why they were invented. In fact, the evolution of these numbers took about three hundred years. In 1545 Jerome Cardan , an Italian mathematician, physician, gambler, and philosopher published a book called Ars Magna The Great Art ). In this he described an algebraic procedure for solving cubic and quartic equations. He also proposed a problem that dealt more with quadratics. He wrote: If some one says to you, divide 10 into two parts, one of which multiplied into the other shall produce...40, it is evident that this case or question is impossible. Nevertheless, we shall solve it in this fashion. Cardan essentially applied the method of completing the square to x + y = 10 and xy = 40 (x - 10x + 40 = 0) to get the numbers,
He multiplied these numbers and got 40. After that, he didn't do much else with this and concluded that the result was "as subtle as it is useless." Complex numbers did not come about from this example, but in connection with the solution to cubic equations.

43. Continued Fractions
The first known examples come from rafael bombelli (ca. 1526 1573), the Italianalgebraist best known for having a wild thought and developing the
http://www.petrospec-technologies.com/Herkommer/contfrac.htm
Continued Fractions
by Mark Herkommer
October 26, 2003
( Excerpted from my book: Number Theory: A Programmer's Guide
Introduction
Number theory has many tools but probably none is more fascinating or elegant than continued fractions. It was once said that God invented the integers and man invented everything else. It might be added God probably invented continued fractions as well. Continued fractions were developed (or discovered) in part as a response to a need to approximate irrational numbers. Since that time they have distinguished themselves as important tools for solving problems in probability theory, analysis, and especially number theory. Continued fractions give us something more than solutions to specific problems. They offer another way to represent real numbers and this affords us an insight obscured by traditional decimal representations. Because continued fractions are be developed using Euclid's algorithm it is tempting to believe that the great geometrician used them, but this is probably not true. The first known examples come from Rafael Bombelli (ca. 1526 - 1573), the Italian algebraist best known for having a "wild thought" and developing the concept of complex numbers (Boyer and Merzbach, 1991). In his Algebra, published in 1572, he gave a reasonable approximation for the square root of 13:
The formal study of continued fractions continued throughout the 17th century with contributions from C. Schwenter and Christiaan Huygens (1629 - 1695). In 1695 John Wallis (1616 - 1703) gave continued fractions a thorough analysis and bestowed on them the name they now bear. In their more general form continued fractions look like:

44. Untitled
However, from this example rafael bombelli s (ca. 15261573) made the first steptoward complex rafael bombelli. Born Jan 1526 in Bologna, Italy
http://www.math.tamu.edu/~don.allen/history/renaissc/renassc.html
Next: About this document
April 2, 1997 Algebra in the Renaissance The general cultural movement of the renaissance in Europe had a profound impact also on the mathematics of the time. Italy was especially impacted. The Italian merchants of the time travelled widely throughout the East, bringing goods back in hopes of making a profit. They needed little by way of mathematics. Only the elementary needs of finance were required.
  • determination of costs
  • determination of revenues
After the crusades, the commercial revolution changed this system. New technologies in ship building and saftey on the seas allows the single merchant to become a shipping magnate. These sedentary merchants could remain at home and hire others to make the journeys. This allowed and required them to make deals, and finance capital, arrange letters of credit, create bills of exchange, and make interest calculations. Double-entry bookkeeping began as a way of tracking the continuous flow of goods and money. The economy of barter was slowly replaced by the economy of money we have today. Needing more mathematics, they inspired the emergence of a new class of mathematician called

45. Two Variable Functions Discussion
Around the same time, rafael bombelli who was studying cubic equations, too invented the operations we saw above for complex numbers.
http://www.shodor.org/interactivate/discussions/2var.html
Two Variable Functions Discussion Student: So I was told that to understand fractals I need to know something about complex numbers. What are they? Mentor: The idea of complex numbers took many years to become accepted. We have a rule in mathematics that we can only take the square root of positive numbers. But there are also lots of negative numbers. Student: So, complex numbers have to do with the square root of negative numbers? Mentor: Exactly. The easiest way to think of complex numbers is as an ordered pair of numbers. Remember how to plot ordered pairs? We use the first as the horizontal movement and the second as the vertical movement. Student: I know this. For example, plotting (1,3) would give: Mentor: Good! To look at fractals we need to be able to work with functions of these pairs of numbers. These functions can be described as "machines." You may remember that before, we would put a number into a function "machine" and it would return a number to us. This time, an ordered pair goes in and an ordered pair comes out. Basic Operations of addition, subtraction, multiplication and division are revised for this new situation as:

46. Pronunciation Guide For Mathematics
rafael bombelli 152672. Napoleon Bonaparte boh nuh part. George Boole 1815-64bool. Boolean boo lee uhn. Jean-Charles de Borda 1733-99
http://waukesha.uwc.edu/mat/kkromare/up.html
Mathematics Pronunciation Guide
A Megametamathematical Guide, for the Diacritally Challenged, of the Proper American English Pronunciation of Terms and Names This guide includes most mathematicians and mathematical terms that may been encountered in high school and the first two years of college. Proper names are generally pronounced as in the original language.
Some entries are obscure and may be useful only in a game of mathematical trivia, e. g. d'Alembert's
mother, the name of the line in a fraction, or who shot Galois.
I have not had the time to include most definitions or accomplishments. The curious person may try searching the internet for such information. However I have given a few, they are indicated with Move the curser to the symbol and wait a second.
D ates include B.C. or A.D. only if the choice is not obvious from the context.
The Guide is not complete, I will be adding more pronunciations and entries as time permits. (I did not give up my day job.) (The red dates and purple pronunciations are not links.)

47. 2000 Spring Colloquium Series
rafael bombelli of Bologna l Algebra, solution of equations, and the beginningsof the complex numbers Host Dr. Richard Davitt
http://www.math.louisville.edu/colloquia.html
1999 Fall Colloquium Series Tentative Schedule Unless noted otherwise, all talks are in the Natural Science Building (NS), Room 212E 4:00 PM - 5:00 PM. Refreshments are in NS 224, 3:30 PM - 4:00 PM.
January 21, 2000
Professor Jacek Wesolowski
Technical University of Warsaw
Additive damage models within a Banach algebra framework Host: Dr. Greg Rempala
January 28, 2000
Professor Slawomir Soletski
Indiana University
Haar null sets: a measure theoretic notion of smallness on non-locally compact groups Host: Dr. Michal Morayne
February 4, 2000
Professor Stan Burris University of Waterloo The algebra of Boole Host: Dr. Keith Kearnes February 11, 2000 Professor Daniel Curtin Northern Kentucky University Rafael Bombelli of Bologna: l'Algebra, solution of equations, and the beginnings of the complex numbers Host: Dr. Richard Davitt Prof. Curtin will give a Math Club talk on Feb. 11 at 12:00. This talk is entitled Mathematical Kombat: Who solved the cubic equation, and why fight about it? February 25, 2000

48. History Of Mathematics
rafael bombelli (15261572 CE). bombelli helped engineer the reclamation of themarshes of the Val di Chiana, which helped springboard his writing of the
http://www.meta-religion.com/Mathematics/Articles/history_of_mathematics.htm

49. Math 489
rafael bombelli François Viète Simon Stevin John Napier Marin Mersenne RenéDescartes Pierre de Fermat Bonaventura Cavilieri Evangelista Toricelli
http://orion.math.iastate.edu/lhogben/classes/math489.html
Math 489 History of Mathematics
Spring 2005
New Information
Final 12-2 PM Monday May 2 in the regular classroom 2 Carver. Extended time is allowed.
4/28 Updated topics list for the final.

The final is comprehensive but also emphasizes material since test 2.
Algebraic Symbolism slides
Index
General Course Information
2:10-3:30 TTh Room 2 Carver Hall Objective
The objective of this course is not merely to know what mathematics was discovered when and by whom, but to understand the how the development of mathematical ideas was influenced by knowledge and notation available, realize the intellectual struggles involved in the development of new mathematical concepts, and appreciate mathematics as a part of human culture.
Text: History of Mathematics: Brief Version, by Victor J. Katz
The course will cover the entire text as outlined in the reading schedule.

50. Mathematicians From DSB
Translate this page bombelli, rafael, 1526-1572. Borchardt, Carl Wilhelm, 1817-1880. Borel, ÉmileFélix-Édouard-Justin, 1871-1956. Bouquet, Jean-Claude, 1819-1885
http://www.henrikkragh.dk/hom/dsb.htm
Last modification: document.write(document.lastModified)
emailaddr('webmaster','henrikkragh.dk','Webmaster','hkssmall');
Validate html
Mathematicians from the Dictionary of Scientific Biography (DSB)
For biographic details of Scandinavian mathematicians (and others), see my link page to DBL (Danish) or to NBL (Norwegian) Abel, Niels Henrik Ampère, André-Marie Argand, Jean Robert Arrhenius, Svante August Artin, Emil Beltrami, Eugenio Berkeley, George Bernoulli, Jakob I Bernoulli, Johann I Bertrand, Joseph Louis François Bessel, Friedrich Wilhelm Bianchi, Luigi Bjerknes, Carl Anton Bjerknes, Vilhelm Frimann Koren Bolyai, Farkas Bolyai, János Bolzano, Bernard Bombelli, Rafael Borchardt, Carl Wilhelm Borel, Émile Félix-Édouard-Justin Bouquet, Jean-Claude Briot, Charles Auguste Bérard, Jacques Étienne Bérard, Joseph Frédéric Cantor, Georg Carathéodory, Constantin Cardano, Girolamo Cauchy, Augustin-Louis Cayley, Arthur Chasles, Michel Chebyshev, Pafnuty Lvovich Clairaut, Alexis-Claude Clausen, Thomas Clebsch, Rudolf Friedrich Alfred Colden, Cadwallader

51. Philosophical Themes From CSL:
Some of these difficulties were later ameliorated by rafael bombelli (152672)whose Algebra (1572) included the first discussion of what we now call
http://myweb.tiscali.co.uk/cslphilos/algebra.htm
Algebra and Geometry in the Sixteenth and Seventeenth Centuries Home Online Articles Links ... Recommend a Friend
Introduction
After outlining the state of algebra and geometry at the beginning of the sixteenth century, we move to discuss the advances in these fields between 1500 and 1640. A separate section is devoted to the development and use of algebraic geometry by Descartes, Fermat and Newton. We close with an attempt to assess the relative importance of these developments.
State of the Arts: Chuquet and Pacioli
At the beginning of the sixteenth century, mathematics was dominated by its Greek heritage and therefore by the study of geometry. But algebra was not wholly absent, and significant advances in notation had been made towards the end of the fifteenth century. Two works were particularly important in this regard: Nicolas Chuquet’s (c.1440-c.1488) Triparty (1484) and Luca Pacioli’s (c.1445-1517) Summa (1494). Pacioli’s symbolism was limited, consisting mostly of abbreviations. Although Chuquet’s symbolism was more advanced, the influence of this work was limited by its very small circulation: it was not properly published until 1880.
Algebraic Advances: Cardano, Bombelli, Viète and Harriot

52. Previous Monthly Problems And Solutions
from ALGEBRA (1572), http//wwwgroups.dcs.st-and.ac.uk80/~history/Bookpages/bombelli4.gif whose author, rafael bombelli, lived from1526 to 1573.
http://mathcentral.uregina.ca/MP/previous2000/
Previous Problems and Solutions
Current Problem
MP12: August 2001
  • You are given five points in the plane and are told that they are the midpoints of the edges of some pentagon. Find the pentagon.
    Given the midpoints of the sides of an n-gon in the plane, is it always possible to determine the n-gon?
  • Solution to August 2001 problem
    MP11: July 2001 An old edition of Ripley's Believe It Or Not states that the number
    N = 526315789473684210
    is a persistent number: if N is multiplied by any positive integer, the resulting product always contains all ten digits 0, 1, 2, ..., 9 (with repetitions, of course).
  • Prove or disprove Ripley's statement.
    Are there any persistent numbers that are smaller than N?
  • Solution to July 2001 problem
    MP10: June 2001 We found this month's problem in Crux Mathematicorum 27:3 (April 2001) pages 204-205 - it is problem 3 from the Ninth Annual Konhauser Problemfest (Carleton College, prepared by David Savitt and Russell Mann. The Problem of the Month for June. a. Begin with a string of 10 A's, B's, and C's, as for example
    A B C C B A B C B A.

    53. Problemas Y Soluciones Anteriores
    Translate this page en ALGEBRA (1572), http//www-groups.dcs.st-and.ac.uk80/~history/Bookpages/bombelli4.gif, cuyo autor, rafael bombelli, vivio desde1526 al 1573.
    http://mathcentral.uregina.ca/MP/sprevious2000/
    Problemas y soluciones anteriores
    Problema Actual
    MP12: agosto, 2001
    MP11: Julio, 2001
    N=526315789473684210
  • Pruebe que el enunciado de Ripley es o bien verdadero, o falso.
  • MP10: Junio, 2001 Encontramos este problema en la revista Crux Mathematicorum El problema de junio: a.
    A B C C B A B C B A.
    A B C C B A B C B A C A C A C C A A C B B B B C B A B B B B A A C C B B C A B C B A B C A C C A B C B C A A A b.
    MP9: Mayo, 2001 El problema de este mes aparece en ALGEBRA http://www-groups.dcs.st-and.ac.uk:80/~history/Bookpages/Bombelli4.gif , cuyo autor, Rafael Bombelli, vivio desde 1526 al 1573. Gracias Rafa. El problema de mayo:
    MP8: Abril, 2001
    El problema del mes de abril es entonces: MP7: Marzo, 2001 MP6: Febrero 2001 El problema del mes entonces es: Problema mensual A Math Central

    54. TeacherSource . Recommended Books . Math | PBS
    Mazur examines the role of imagination and imagery in poetry and mathematics,reviewing the work of Girolamo Cardano and rafael bombelli.
    http://www.pbs.org/teachersource/recommended/math/bk_basiccomputation.shtm
    search options
    Tuesday, August 30, 2005
    Recommended Books
    Archived Recommendations
    Basic Computation
    7 X 9 = Trouble!
    By Claudia Mills and G. Brian Karas
    Published April 2002
    Grade Level: 3-5
    Wilson Williams is having trouble learning his times tables. He wishes he were smarter. His parents try to help, but practicing isn’t as much fun as playing. When he fails his 3s again, Wilson’s teacher sends home a note, and Wilson can only see weeks of trouble ahead.
    Amazing Pop-Up Multiplication Book
    By Kate Petty and Jennie Maizels Published September 1998 Grade Level: 3-5, 6-8 The authors who brought you the highly acclaimed Amazing Pop-Up Grammar Book have done it again! Readers in grades 3-6 will love the elaborate illustrations that slide and pop-up to reveal math questions and answers. The book is organized by the numbers 1-10; each number provides practice on a specific part of the multiplication table through scenarios like Noah's Ark, finding clothes in drawers and closets, and much more. Apple Fractions By Jerry Pallotta and Rob Bolster Published October 2002 Grade Level: PreK-2, 3-5

    55. Complex Numbers And Geometry
    A short time later, in 1572, another mathematician, rafael bombelli helped toshape the nature of algebra for the next 400 years.
    http://campus.northpark.edu/math/PreCalculus/Transcendental/Trigonometric/Comple
    Section 5.1: Complex Numbers and Geometry
    While the quadratic formula , has been known to give solutions to the quadratic equation, ax bx c = , since the time of the ancient Babylonian civilization (around 2000 BC), the simple looking equation, x + 1 = 0, was an enigma until relatively recently. That is because our number concept has historically been limited to those numbers which can be graphed on the real number line. In this section, we will see how the real number system is only a part of a larger number system, call the "complex" numbers. Moreover, we will see how the nice geometric interpretations of addition, multiplication, and negation of real numbers generalize to the complex numbers . We will also learn about a new operation, which applies to complex numbers, called conjugation , and discuss its geometric significance.
    The Origins of Complex Numbers
    For thousands of years, mathematicians considered the equation x + 1 = to be insolvable. From a functional point of view, we know that the range of the square function f x x , contains only positive numbers, so that

    56. A Look To The Past
    In 1572 rafael bombelli (15261573) published his treatise, Algebra, in which hegave one more step in the solution of cubic equations, expressing solutions
    http://ued.uniandes.edu.co/servidor/em/recinf/tg18/Vizmanos/Vizmanos-2.html
    Will elementary algebra disappear with the use of new graphing calculators?.
    A look to the past
    What do we understand elementary algebra to be? Elementary algebra is the language with which we communicate the majority of mathematics. Thanks to algebra we can work with concepts at an abstract level and then apply them. Elementary algebra begins as a generalization of arithmetic and then focuses on its own structure and greater logical coherence. From there comes the importance of the various uses of algebraic symbols. When we write A + B, we can be indicating the sum of two natural numbers, the sum of two algebraic expressions, or even the sum of two matrices. Thus there is, at first, representations and symbolism, and later the development of algorithms and procedures to work formally with algebraic expressions. But what we today understand to be algebra has been the fruit of the efforts of many generations that have been contributing their grains of sand in constructing this magnificent building. It seems that the Egyptians already knew methods for solving first degree equations. In the

    57. Practical Foundations Of Mathematics
    For example rafael bombelli ( c. 1560) would write. RcL 2 p. di m. 11 L for our3Ö{2+11i}. Many professional mathematicians to this day use the quantifiers
    http://www.cs.man.ac.uk/~pt/Practical_Foundations/html/s10.html
    Practical Foundations of Mathematics
    Paul Taylor
    Chapter 1
    First Order Reasoning
    How do we begin to lay the foundations of a palace which is already more than 3600 years old? Alan Turing [ ] identified what is perhaps the one point of agreement between the Rhind papyrus and our own time, that a ``computer'' ( ie a mathematician performing a calculation) puts marks on a page and transforms them in some way. Even in its most naive form, Mathematics is not passive: we recite the multiplication table, transforming xx y z ) may be replaced by ( xxy xxz ). We say that these pairs are respectively equal , meaning that they denote the same objects in ``reality,'' even though they are written in different ways. During the process of calculation (from Latin calx , a pebble) there are intermediate forms with no directly explicable meaning: accountants refer to ``net'' and ``gross'' amounts, and to ``pre-tax'' profits, in an attempt to give them one. The remarkable feature of mathematics is that we may suspend belief like this, and yet rely on the results of a lengthy calculation, even when it has been delegated to a computer. The notation of elementary school arithmetic, which nowadays everyone takes for granted, took centuries to develop. There was an intermediate stage called

    58. Progetto Polymath - I Numeri Complessi: Un Percorso Didattico Tra Algebra E Geom
    Translate this page Scipione Dal Ferro, Girolamo Cardano, rafael bombelli e numerosi altri. i numeri allora conosciuti con altri numeri, fu rafael bombelli (1526-1573),
    http://www2.polito.it/didattica/polymath/htmlS/argoment/APPUNTI/TESTI/Dic03/Cap2
    Indice
    Elementi
    e con p ed q
    Girolamo Cardano (1501-1576) Ars Magna , si ottiene la formula seguente: si ritrova descritta nelle celebri terzine di Tartaglia ( a destra si riporta la scrittura algebrica attuale): "Quando che’l cubo con le cose appresso Trovan dui altri differenti in esso. Da poi terrai questo per consueto Al terzo cubo delle cose neto, El residuo poi suo generale Delli lor lati cubi ben sottratti Ars Magna come uno degli autori della scoperta.
    Ars Magna e Cardano attribuisce a Ferrari il metodo.
    Bombelli, nella sua opera irriducibile
    Algebra
    Algebra Bombelli prende in esame le radici immaginarie delle equazioni, che egli chiama " ", e giunge ad operare con i numeri che noi oggi chiamiamo "complessi". Bombelli introdusse i termini e meno di meno , per indicare + i e - i , che abbrevia nelle scritture pdm e mdm ; ad esempio, con:
    R c pdm
    Nel linguaggio di Bombelli, queste regole si esprimono nel seguente modo: Meno di meno via men di meno, fa meno.

    59. Progetto Polymath - Antologia - L'algebra Astratta
    rafael bombelli (cheè del 1581), rischia di non riconoscere la più semplice equazione,
    http://www2.polito.it/didattica/polymath/htmlS/info/Antologia/Lombardo.htm
    di Lucio Lombardo Radice solo tecnica e non anche cultura generale; solo calcolo e non anche Lucio Lombardo Radice Non ho tempo Mario Garriba, protagonista del film di Ansano Giannarelli Non ho tempo Tenne inoltre l'insegnamento di Storia della Matematica nella "Scuola di Perfezionamento in Matematica e Fisica", di cui fu vice-direttore dal febbraio 1963 al 1966. Lombardo Radice, membro del comitato centrale del PCI, si impegnò per il rinnovo della scuola italiana, rivendicando in particolare, per la matematica, l’importanza della storia della matematica nell’insegnamento, indispensabile per la comprensione delle teorie e dei risultati. Si occupò in particolare di geometrie finite e di geometrie combinatorie lavorando insieme a Beniamino Segre e a Guido Zappa. Mario Garriba in un altro fotogramma del film Non ho tempo di Ansano Giannarelli.

    60. New Dictionary Of Scientific Biography
    Translate this page bombelli, rafael Bonnet, Pierre-Ossian Boole, George Borchardt, Carl WilhelmBorda, Jean-Charles Borel, Émile Borelli, Giovanni Alfonso Borsuk, Karol
    http://www.indiana.edu/~newdsb/math.html
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