# PI number

The history of science constitutes an important part in the history of man, mainly in the area of mathematics . Many terms and concepts have emerged over time as a result of these studies and the number is probably seen as the most important numerical constant and studied throughout the history of the world and of mathematics. Its meaning, although apparently only includes mathematical aspects, has come to go beyond the different frontiers of this discipline, monopolizing the interest of men in many different areas of knowledge .

## What is the number pi?

The number pi is a number widely used in the area of mathematics that represents a constant and that is used in the areas of physics , engineering , physics and mathematics , and that has infinite decimal places .

• Definition
• Characteristics of the number pi
• Source
• History
• Who discovered the number pi
• Properties
• Applications
• How much does it cost
• How the number pi is represented
• Importance
• Curiosities

## Definition

The number pi can be seen as one of the most studied numbers in the area of mathematics . It is a number that has decimal places in infinite quantities and represents one of the most important mathematical constants in mathematics , physics, and engineering . It is also one of the most widely used mathematical constants in physics equations , along with the number e . In other words, we can say that the number pi is the constant that is responsible for relating the perimeter of a circle with the amplitude of its diameter:Π = L / D.

## Characteristics of the number pi

Some of the most important characteristics of the number pi are the following:

• The number pi fits into the well-known irrational numbers , this because it is not an exact number but rather it is an infinite number, with infinite decimal places.
• As a symbol of the number pi, the Greek letter pi or π is used.
• Its name comes from the Greek periphereia , a term used to designate the perimeter of a circle.
• Every March 14, World Pi Number Day is celebrated.

## Source

Regarding its origin, it is considered that in 2,000 BC the Babylonians had tried to find out the circumference of a circle and that they considered it to be a little more than three times the equivalent of its diameter. But it was in 225 BC when Archimedes of Syracuse began his mathematical theory which little by little was perfected and in 1706 the mathematician William Jones used his symbol π for the first time , although it was later Leonhard Euler who popularized it. .

## History

The history of the number pi can be divided into three well-established periods , which differ from each other by aspects concerning the method, immediate purposes and the scientific and intellectual tools available. The first period goes from the first empirical records of the relationship of the perimeter of a circumference and its diameter to the invention of the differential and integral calculus in the middle of the seventeenth century.

The second period begins with the discovery of the infinitesimal calculus and lasted approximately a century, and was characterized by the application of analytical methods to determine expressions for calculus that included trigonometric functions .

The third period spanned from the mid- 18th century to the late 19th century , and in this period there was great attention to critical investigations into the true nature of the number itself. In this period, the number pi is recognized as an irrational and transcendental number .

## Who discovered the number pi

The current name of the number was first used by William Oughtred , though popularized by Leonhard Euler.  Before this, the number pi was known as the “Ludolph constant” or as the “Archimedean constant .

## Properties

The properties of the number pi are as follows:

• Pi is an irrational number , which means that it cannot be written as a fraction or as a whole number.
• In other words, the decimals of Pi are not predictable and no model could predict them.
• Pi is a transcendental number , in other words it cannot be the solution of any equation of polynomials with integer coefficients.
• It is a universal number that contributes considerably to the fascination that still endures around Pi.

## Applications

The number pi helps us to know the length of a circumference , in other words the perimeter, it also serves to know its surface  or area . It is a number that we find in spheres , cones , cylinders , ellipses , and in nature , so thanks to it it has been possible to build, build , design , etc. It serves as a mathematical tool to break down a signal into constitutive frequencies , a tool that is very important in voice conversionto text from voice assistants. When making a location on a map using GPS , most of the Pi methods are part of the calculation .

## How much does it cost

Pi is the number that can be obtained when the length of a circle is divided by its diameter and can be rounded as 3.141592.

## How the number pi is represented

The number pi is represented by a Greek letter that is written as follows: π.

## Importance

The number pi is very important for the world of mathematics because it is thanks to it that we can measure the different circumferences and diameters that circular objects or circles have. It is also important in the area of computer science for the correct realization of the calculations carried out by computers , so that they are more precise.

## Curiosities

Some curiosities that we can observe regarding the number pi are the following:

• The number pi is such a globally acclaimed number that it even has its own celebration . On March 14 (3/14) at 01:59 pm is the peak time of celebration, this six – digit approximation: 3.14159.
• The English mathematician William Shanks managed to obtain 707 decimal places of the number pi after conducting a research work in 1853.
• In 1957 the computer known as Pegasus was used to calculate decimals of pi, to finally get 7,840 decimal places.
• In 1961, and using an IBM 7090 computer , it was possible to arrive at 000 decimal places of pi.
• If we could write in a straight line the first 000 million of decimals of Pi, by placing five digits per linear centimeter of paper, the strip would be so long that might take a turn to the circumference of the Earth .