# Writing a rational number as a decimal

The tenths decimal place is the digit immediately to the right of the decimal point, such as the 5 in

History of ancient numeral systems Bones and other artifacts have been discovered with marks cut into them that many believe are tally marks. A tallying system has no concept of place value as in modern decimal notationwhich limits its representation of large numbers.

Nonetheless tallying systems are considered the first kind of abstract numeral system. The number in Khmer numeralsfrom an inscription from AD. An early use of zero as a decimal figure. He gave rules of using zero with negative and positive numbers, such as 'Zero plus a positive number is the positive number, and a negative number plus zero is the negative number'.

The Brahmasphutasiddhanta is the earliest known text to treat zero as a number in its own right, rather than as simply a placeholder digit in representing another number as was done by the Babylonians or as a symbol for a lack of quantity as was done by Ptolemy and the Romans.

The use of 0 as a number should be distinguished from its use as a placeholder numeral in place-value systems. Babylonian and Egyptian texts used it. Indian texts used a Sanskrit word Shunye or shunya to refer to the concept of void.

In mathematics texts this word often refers to the number zero. There are other uses of zero before Brahmagupta, though the documentation is not as complete as it is in the Brahmasphutasiddhanta.

Because it was used alone, not as just a placeholder, this Hellenistic zero was the first documented use of a true zero in the Old World. Another true zero was used in tables alongside Roman numerals by first known use by Dionysius Exiguusbut as a word, nulla meaning nothing, not as a symbol.

These medieval zeros were used by all future medieval computists calculators of Easter. An isolated use of their initial, N, was used in a table of Roman numerals by Bede or a colleague abouta true zero symbol.

History of negative numbers The abstract concept of negative numbers was recognized as early as —50 BC in China. The Nine Chapters on the Mathematical Art contains methods for finding the areas of figures; red rods were used to denote positive coefficientsblack for negative. During the s, negative numbers were in use in India to represent debts.

At the same time, the Chinese were indicating negative numbers by drawing a diagonal stroke through the right-most non-zero digit of the corresponding positive number's numeral. He used them as exponentsbut referred to them as "absurd numbers".

Rational numbers [ edit ] It is likely that the concept of fractional numbers dates to prehistoric times. The Ancient Egyptians used their Egyptian fraction notation for rational numbers in mathematical texts such as the Rhind Mathematical Papyrus and the Kahun Papyrus.

Classical Greek and Indian mathematicians made studies of the theory of rational numbers, as part of the general study of number theory. Of the Indian texts, the most relevant is the Sthananga Sutrawhich also covers number theory as part of a general study of mathematics.

The concept of decimal fractions is closely linked with decimal place-value notation; the two seem to have developed in tandem. For example, it is common for the Jain math sutra to include calculations of decimal-fraction approximations to pi or the square root of 2.

The story goes that Hippasus discovered irrational numbers when trying to represent the square root of 2 as a fraction. However Pythagoras believed in the absoluteness of numbers, and could not accept the existence of irrational numbers.

He could not disprove their existence through logic, but he could not accept irrational numbers, and so, allegedly and frequently reported, he sentenced Hippasus to death by drowning, to impede spreading of this disconcerting news.

It had remained almost dormant since Euclid. Inthe publication of the theories of Karl Weierstrass by his pupil E. Weierstrass's method was completely set forth by Salvatore Pincherleand Dedekind's has received additional prominence through the author's later work and endorsement by Paul Tannery Weierstrass, Cantor, and Heine base their theories on infinite series, while Dedekind founds his on the idea of a cut Schnitt in the system of real numbersseparating all rational numbers into two groups having certain characteristic properties.

The search for roots of quintic and higher degree equations was an important development, the Abel—Ruffini theorem RuffiniAbel showed that they could not be solved by radicals formulas involving only arithmetical operations and roots. Hence it was necessary to consider the wider set of algebraic numbers all solutions to polynomial equations.

Galois linked polynomial equations to group theory giving rise to the field of Galois theory. Transcendental numbers and reals [ edit ] Further information: Finally, Cantor showed that the set of all real numbers is uncountably infinite but the set of all algebraic numbers is countably infiniteso there is an uncountably infinite number of transcendental numbers.

Infinity and infinitesimals [ edit ].Win Corduan. This site is composed of entries from my blog over the spring and summer of The topic will introduce itself and needs no further explanation. As usual, I'm retaining the somewhat informal style of a blog entry, though I've removed most of the purely.

extraneous and personal content.. This site is distributed over a number of . Learning algebra is a little like learning another language. In fact, algebra is a simple language, used to create mathematical models of real-world situations and .

Rounding is a process by which you can write a long number as a shorter number with roughly the same value. The tenths decimal place is the digit immediately to the right of the decimal point, such as the 5 in , so to round it out you need to look at the number to its right, which is the hundredths decimal .

For example, when you want to convert 6 1/2 into a decimal form, you keep the 6, work the division to convert 1/2 into a decimal – the result is – and then add the two together for a result of Definition of rational - based on or in accordance with reason or logic, (of a number, quantity, or expression) expressible, or containing quantities which.

In this lesson, we will learn about rational numbers and their characteristics. We'll discover what they are, what they aren't and how to.

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