переведи текст на русский MATHEMATICS DEVELOPMENT 
17th Century Mathematic 
The scientific revolution of the 17th century spurred advances in mathematics 
as well. The founders of modern science – Nicolaus Copernicus, Johannes Kepler, 
Galileo, and Isaac Newton – studied the natural world as mathematicians, and they 
looked for its mathematical laws. Over time, mathematics grew more and more 
abstract as mathematicians sought to establish the foundations of their fields in logic. 
The 17th century opened with the discovery of logarithms by the Scottish 
mathematician John Napier and the Swiss mathematician Justus Byrgius. 
Logarithms enabled mathematicians to extract the roots of numbers and simplified 
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many calculations by basing them on addition and subtraction rather than on 
multiplication and division. 
Napier, who was interested in simplification, studied the systems of the Indian 
and Islamic worlds and spent years producing the tables of logarithms that he 
published in 1614. Kepler’s enthusiasm for the tables ensured their rapid spread. 
The 17th century saw the greatest advances in mathematics since the time of 
ancient Greece. The major invention of the century was calculus. Although two great 
thinkers – Sir Isaac Newton of England and Gottfried Wilhelm Leibniz of Germany – have received credit for the invention, they built on the work of others. As Newton 
noted, “If I have seen further, it is by standing on the shoulders of giants.” Major 
advances were also made in numerical calculation and geometry. 
Gottfried Leibniz was born (1st July, 1646) and lived most of his life in 
Germany. His greatest achievement was the invention of integral and differential 
calculus, the system of notation which is still in use today. In England, Isaac Newton 
claimed the distinction and accused Leibniz of plagiarism, that is stealing somebody 
else’s ideas but stating that they are original. Modern-day historians, however, regard 
Leibniz as having arrived at his conclusions independently of Newton. They point out 
that there are important differences in the writings of both men. 
Differential calculus came out of problems of finding tangents to curves, and 
an account of the method is published in Isaac Barrow’s “Lectiones geometricae” 
(1670). Newton had discovered the method (1665-66) and suggested that Barrow 
include it in his book. 
Leibniz had also discovered the method by 1676, publishing it in 1684. Newton 
did not publish his results until 1687. A bitter dispute arose over the priority for the 
discovery. In fact, it is now known that the two made their discoveries independently 
and that Newton had made it ten years before Leibniz, although Leibniz published 
first. The modern notation of dy/dx and the elongated s for integration are due to 
Leibniz. 
The most important development in geometry during the 17th century was the 
discovery of analytic geometry by Rene Descartes and Pierre de Fermat, working 
in dependently in France. Analytic geometry makes it possible to study geometric 
figures using algebraic equations. By using algebra, Descartes managed to overcome 
the limitations of Euclidean geometry. That resulted in the reversal of the historical 
roles of geometry and algebra. 
The French mathematician Joseph Louis Lagrange observed in the 18th 
century, “As long as algebra and geometry proceeded along separate paths, their 
advance was slow and their applications limited. But when these sciences joined 
company, they drew from each other fresh vitality and thenceforward marched on at a 
rapid pace toward perfection.” 
Descartes’ publications provided the basis for Newton’s mathematical work 
later in the century. Pierre de Fermat, however, regarded his own work on what 
became known as analytic geometry as a reformulation of Appollonius’s treatise on 
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conic sections. That treatise had provided the basic work on the geometry of curves 
from ancient times until Descartes. 
18th – 19th Century Mathematics 
During the 18th century, calculus became the cornerstone of mathematical 
analysis on the European continent. Mathematicians applied the discovery to a 
variety of problems in physics, astronomy, and engineering. In the course of doing so, 
they also created new areas of mathematics. 
In France, Joseph Louis Lagrange made substantial contributions in all fields of 
pure mathematics, including differential equations, the calculus of variations, 
probability theory, and the theory of equations. In addition, Lagrange put his 
mathematical skills to work in the solution of practical problems in mechanics and 
astronomy. 
The greatest mathematician of the 18th century, Leonard Euler of Switzerland, 
wrote works that covered the entire fields of pure and applied mathematics. He wrote 
major works on mechanics that preceded Lagrange’s work. He won a number of 
prizes for his work on the orbits of comets and planets, the field known as celestial 
mechanics. But Euler is best known for his works in pure mathematics. In one of his 
works, Introduction to the Analysis of Infinites, published in 1748, he approached 
calculus in terms of functions rather than the geometry of curves. Other works by 
Euler contributed to number theory and differential geometry (the application of 
differential calculus to the study of the properties of curves and curved spaces). 
Mathematicians succeeded in firming the foundations of analysis and 
discovered the existence of additional geometries and algebras and more than one 
kind of infinity. 
The 19th century began with the German mathematician Carl Frederich 
Gauss. He ranks as one of the greatest mathematicians of the world. His book 
Inquiries into Arithmetic published in 1801 marks the beginning of modern era in 
number theory. 
Gauss called mathematics the queen of sciences and number theory the queen 
of mathematics. Almost from the introduction of calculus, efforts had been made to 
supply a rigorous foundation for it. Every mathematician made some effort to 
produce a logical justification for calculus and failed. Although calculus clearly 
worked in solving problems, mathematicians lacked rigorous proof that explained 
why it worked. Finally, in 1821, the French mathematician Augustin Louis Cauchy 
established a rigorous foundation for calculus with his theory of limits, a purely 
arithmetic theory. 
Later, mathematicians found Cauchy’s formulation still too vague because it 
did not provide a logical definition of real number. The necessary precision for 
calculus and mathematical analysis was attained in the 1850s by the German 
mathematician Karl T. W. Weierstrass and his followers. 
Another important advance in analysis came from the French mathematician 
Jean Baptiste Fourier, who studied infinite series in which the terms are 
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trigonometric functions. Known today as Fourier series, they are still powerful tools 
in pure and applied mathematics. 
The investigation of Fourier series led another German mathematician, Georg 
Cantor, to the study of infinite sets and to the arithmetic of infinite numbers. Georg 
Cantor began his mathematical investigations in number theory and went on to create 
set theory. In the course of his early studies of Fourier series, he developed a theory 
of irrational numbers. Cantor and another German mathematician, Julius W. R. 
Dedekind, defined the irrational numbers and established their properties. These 
explanations hastened the abandonment of many 19th century mathematical 
principles. When Cantor introduced his theory of sets, it was attacked as a disease 
from which mathematics would soon recover. However, it now forms part of the 
foundations of mathematics. The application of set theory greatly advanced 
mathematics in the 20th century.