Rule one? =- 1, and I can use real numbers to perform four operations according to the same algorithm, and I is called imaginary unit. The power of imaginary unit I is periodic, and the imaginary unit is expressed by I, which was put forward by Euler in 1748's infinitesimal analysis theory, but it did not attract attention. 180 1 year is widely used after being used by Gaussian system.

Source:

The imaginary unit "I" was first invented by the Swiss mathematician Euler, and was not widely used until the German mathematician Gauss advocated it. Gauss first introduced the term "complex number" and recorded it as a+bi. The word "imaginary number" was first put forward by Descartes. As early as 1800, someone used (a, b) to represent a+bi. They may be Curtis, Demovo, Euler and Vandermonde,.

Casbas Veisser, a Norwegian, was the first to express a+bi as a vector, and he was the first to give a vector algorithm for complex numbers. The symbol "I" comes from the French imkginaire-the first letter of "virtual", not from the English imaginarynumber (or imaginaryquautity). The complex set c comes from the first letter of the English word complexnumber.

Extended data:

Extension related to I: the definition of I in physics;

The intensity of current is described by current intensity, which is the amount of electricity passing through a certain section of a conductor in unit time, referred to as current for short, and expressed by I.

The current intensity is scalar, and the direction of positive charge is defined as the direction of current. The direction of current in a conductor always points from high potential to low potential along the direction of electric field. In the international system of units, the unit of current intensity is ampere (A), which is one of the seven basic units in the international system of units.

Some common currents: electronic watch 1.5μA to 2μA, incandescent bulb 200mA, mobile phone 100mA, air conditioner 5A to 10A, high voltage 200A, lightning 20000A to 200000A.

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