π = sin (180 ÷ n) × n formula is derived from an infinite polygon with a positive circle. When this formula n=∞ and the error rate of π is 0, π = sin (180 ÷1×10) × 66.

1, 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 common mathematical constant in mathematics and physics.

2.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 sin x = 0.

Extended data:

First, the first definition of a circle.

1, the set of points whose distance to a fixed point in the same plane is equal to a fixed length is called a circle. This fixed point is called the center of the circle.

2. The length of the circle is the circumference of the circle. Two overlapping circles are called equal circles, and equal circles have numerous symmetry axes.

3. A circle is a regular n polygon (n is an infinite positive integer), and its side length is infinitely close to 0 but can never be equal to 0.

Second, the second definition of circle:

1, the ratio of the distance between a moving point and two fixed points on the plane (or the ratio of the square of the distance) is equal to a constant that is not 1, then the trajectory of this moving point is a circle.

2. It is proved that the coordinates of points are (x 1, y 1) and (x2, y2), the moving point is (x, y), and the distance ratio is k, which is determined by the distance formula of two points. Satisfy the equation (x-x 1) 2+(y-y1) 2 = k2× [(x-x2) 2+(y-y2) 2] When k is not1,a cyclic equation is obtained.

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