A circle is a geometric figure. When a line segment rotates around one endpoint on a plane, the trajectory of the other endpoint is called a circle. By definition, compasses are usually used to draw circles. ?

Pi, generally expressed by π, is a common mathematical constant in mathematics and physics. It is defined as the ratio of the circumference to the diameter of a circle. It is also equal to the ratio of the area of a circle to the square of its radius. Accurate calculation of geometric shapes such as circle perimeter, circle area and sphere volume is the key value. In the analysis, π can be strictly defined as the smallest positive real number x satisfying sin(x) = 0.

Zu Chongzhi (429-500) was an outstanding mathematician and scientist in China. People in the Southern and Northern Dynasties, Han people, the word Wen Yuan. Born in Yuanjia for six years, he died in Hou Yongyuan and Qi Hun for two years. My ancestral home is in Qixian County, Fanyang County. In order to escape the war, Zu Chongzhi's grandfather, Zuchang, moved from Hebei to Jiangnan.

Zuchang was once a "great craftsman" in Liu Song, in charge of civil engineering; Zu Chongzhi's father is also a DPRK official. Zu Chongzhi received scientific knowledge from his family since childhood. When I was young, I entered Hualin University and engaged in academic activities. Throughout his life, he served as an official in South Xuzhou (now Zhenjiang City), such as Shi and Fu joining the army, Lou County Order (now northeast Kunshan City), Servant Shooter and Changshui Captain.