The five-pointed star has 30 segments.
Each side of the five-pointed star is divided into three parts, and each part is a unit. One unit has 5*3= 15 line segments, two units have 5*2= 10 line segments, and three units have 5 line segments, that is, the edge of a five-pointed star,15+/kloc-0+5 = 30 line segments, and * * has 30 line segments.
The five-pointed star is a common geometric figure, which can be used as a design element of national flags, badges and other signs. For example, the stars on the American flag are pentagrams, while the five stars on the China flag are pentagrams surrounded by a regular Pentagon.
The five-pointed star also has important applications in mathematics and physics. In geometry, the five-pointed star can be used to study the properties and symmetry of plane figures; In physics, the five-pointed star can be used to describe the propagation of electromagnetic waves and light.
Properties of pentagram
1, sum of internal angles: the sum of internal angles of the five-pointed star is 540 degrees. This is because the pentagram can be decomposed into five triangles, and the sum of the internal angles of each triangle is 180 degrees, so the sum of the internal angles of the pentagram is 5× 180 degrees =540 degrees.
2. Fibonacci sequence: The structure of the five-pointed star is related to Fibonacci sequence. Fibonacci series is a series that starts with 0 and 1, and each subsequent term is the sum of the previous two terms. When we draw a rectangular figure of Fibonacci sequence, and connect it with the corners as the center, the figure we get happens to be a five-pointed star.
3. The golden section: The five-pointed star is also closely related to the golden section. The golden section refers to dividing a line segment into two parts so that the ratio of one part to the total length is equal to the ratio of the other part to this part. The ratio of the side length to the diagonal of the five-pointed star is the golden section ratio (about 1.6 18), which is widely used in architecture, art and other fields.