Dictionary > Logarithm

Logarithm

Logarithm
(Science: mathematics) One of a class of auxiliary numbers, devised by john napier, of Merchiston, Scotland (1550-1617), to abridge arithmetical calculations, by the use of addition and subtraction in Place of multiplication and division.
The relation of logarithms to common numbers is that of numbers in an arithmetical series to corresponding numbers in a geometrical series, so that sums and differences of the former indicate respectively products and quotients of the latter; thus 0 1 2 3 4 indices or logarithms 1 10 100 1000 10,000 numbers in geometrical progression Hence, the logarithm of any given number is the exponent of a power to which another given invariable number, called the base, must be raised in order to produce that given number. Thus, let 10 be the base, then 2 is the logarithm of 100, because 10^2 = 100, and 3 is the logarithm of 1,000, because 10^3 = 1,000. Arithmetical complement of a logarithm, the difference between a logarithm and the number ten. Binary logarithms. See binary. Common logarithms, or Brigg’s logarithms, logarithms of which the base is 10; so called from henry Briggs, who invented them. Gauss’s logarithms, tables of logarithms constructed for facilitating the operation of finding the logarithm of the sum of difference of two quantities from the logarithms of the quantities, one entry of those tables and two additions or subtractions answering the purpose of three entries of the common tables and one addition or subtraction. They were suggested by the celebrated german mathematician Karl Friedrich gauss (died in 1855), and are of great service in many astronomical computations. Hyperbolic, or Napierian, logarithms, those logarithms (devised by john Speidell, 1619) of which the base is 2.7182818; so called from napier, the inventor of logarithms. Logistic or Proportionallogarithms.
Origin: gr. Word, account, proportion – number: cf. F. Logarithme.


You will also like...

Salmon jumping upstream in the river
Lotic Communities & Animals

A running water environment offers numerous microhabitats for many types of animals. Similar to plants, animals in lotic..

Hominid
The Hominids

The hominid family diversified from the apes around 6 to 8 million years ago. Since then, the evolutionary path has prov..

Principles of Hormonal Control Systems
Principles of Hormonal Control Systems

Hormones are essential in the regulation of the activity of the various biological systems of the human body. The ineffi..

Young plant growing from the soil.
Soils

Nutrients in the soil are essential to the proper growth of a land plant. This tutorial deals with the properties of soi..

primitive arthropods
Arthropods

The arthropods were assumed to be the first taxon of species to possess jointed limbs and exoskeleton, exhibit more adva..

New Zealand Fauna
New Zealand’s Unique Fauna

Meet some of New Zealand's unique fauna, including endemic insects, frogs, reptiles, birds, and mammals, and investigate..