π (π) generally refers to pi (the ratio of circumference to diameter of a circle).
Pi is the ratio of the circumference to the diameter of a circle, which is generally expressed by the Greek letter π and is a universal mathematical constant in mathematics and physics. π is also equal to the ratio of the square of the area and radius of a circle, which is the key value to accurately calculate the geometric shapes such as the circumference of a circle, the area of a circle and the volume of a ball. In the analysis, π can be strictly defined as the smallest positive real number x satisfying sinx=0.
Data expansion:
introduce
Pi refers to the ratio of circumference to diameter of a circle, that is, pi = circumference ÷ diameter, which is generally expressed by the Greek letter π and is a common mathematical constant in mathematics and physics.
π is also equal to the ratio of the square of the area and radius of a circle, that is, π = the area of a circle ÷ radius 2 is the key value to accurately calculate the geometric shapes such as the circumference of a circle, the area of a circle, the volume of a sphere, etc. In the analysis, π can be strictly defined as the smallest positive number x satisfying sinx=0.
Pi is written in the Greek letter π (pronounced [pa? ]), which is a constant (approximately equal to 3. 14 1592654), is the ratio of circumference to diameter. It is an irrational number, that is, an infinite cycle decimal. In daily life, pi is usually expressed as 3. 14, which is used for approximate calculation.
3. The nine decimal places of141592654 are enough for general calculation. Even if engineers or physicists want to make more accurate calculations, they only need to take the values to a few hundred decimal places at best.
characteristic
It is of little practical significance to calculate the value of pi so accurately. A dozen pi values used in modern science and technology are enough. If the Hubble volume is calculated by using the 39-bit precision pi value, the error is less than the volume of an atom.
In the past, people calculated pi to explore whether pi circulated decimals. Since Lambert proved that pi is irrational in 176 1 and Lin Deman proved that pi is transcendental in 1882, the mystery of pi has been uncovered.
algebra
π is an irrational number, that is, it cannot be expressed as the ratio of two integers, which was proved by German scientist johann heinrich lambert in 176 1. In 1882, Lin Deman proved that π is a transcendental number, that is, π cannot be the root of any integer coefficient polynomial.