If AB = N (A> 0, A 1), B is called a logarithm of the bottom N, rejected B = ㏒an. When A = 10 is called analog log, and A = E, natural logarithm is called natural logarithm.
At the end of the 16th century, at the beginning of the 17th century, at the time of the development of natural sciences (especially astronomy), a large number of precision and huge numerical calculations were often encountered, so that mathematicians invented the logarithm in order to seek simplification.
Germany's histori (1487-1567) In the "integer arithmetic" in 1544, two numbers were written, the left is equal to the number (name), the right side is a parameter column (name) Representative, or claim index, German is exponent, representative meaning).
For the left side of the streak (quotient), as long as the representative (index) and (poor), then this and (poor) the original number of the left, the original number is what The accumulation (business), unfortunately, there is no further exploration, no concept of logarithm.
Napier has quite studies on numerical calculation. The "Nadel Certificate", which he makes it makes, simply computing, and its principle is to replace the multi-division. The motivation of his inventive logs is to seek a simple method of spherical triangulation, and he constructs a so-called logarithmic method according to a very unique idea of quality exercise, and its core thinking is the connection between arithmetic numbers and geometry. In his "Wonderful Table Description", the logarithmic principle is known, and the future generation is called Napier logarithm, remembers NAP. ㏒X, it is related to natural logarithm
NAP. ㏒X = 107 ㏑ (107 / x) It can be seen that Napier logs are neither natural logarithm, nor commonly used logaries, and have a certain distance from today's logarithm.
Switzerland's (1552-1632) also found logarithm, possibly Banpir, but published later (1620).
British Brigs created commonly logged logs in 1624.
In 1619, the "new logarithm" of London Since made the logarithmocity with the natural logarithm (with E = 2.71828 ... for the end).
The logarithmic invention has an important influence in the development of society at the time, as scientists Galist (1564-1642) said: "Give me time, space and logarithm, I can create a universe." Another example is the 18th century mathematician Laplas (1749-1827) also mentioned: "Double the time to reduce the life of the astronomer" for the time to reduce the life of the astronomer.
The total number of logaries that were previously introduced in my country was "proportional and logarithm", which was composed of Poland's Munis (1611-1656) and Xue Fengqi in my country in the 17th century. At that time, in LG2 = 0.3010, 2 called "true numbers", 0.3010 called "false number", true and false number of tables, so that the logarithm table is called. Later, the "false number" is "log".
my country's Qing Dynasty, Daiji (1805-1860) developed a variety of Jieji, with "Outlook on Dialect" (1845), "Simplified Separation" (1846). In 1854, the UK's mathematician Amy (1825-1905) was greatly sighed after seeing these works.
