Zu Chongzhi (AD 429-500) was born in Laiyuan County, Hebei Province during the Northern and Southern Dynasties. He read many books on astronomy and mathematics since childhood, studied hard and practiced hard, and finally made him an outstanding mathematician and astronomer in ancient China.
Zu Chongzhi's outstanding achievement in mathematics is about the calculation of pi. Before the Qin and Han Dynasties, people took "diameter of one week and three weeks" as π, which was called "ancient rate". Later, it was found that the error of ancient rate was too big, and pi should be "the diameter of the circle is one and greater than Wednesday", but there are different opinions on how much is left. Until the Three Kingdoms period, Liu Hui put forward a scientific method to calculate pi-"secant method", that is, to approximate the circumference of a circle with the circumference of inscribed regular polygons. Liu Hui calculated a polygon with 96 sides inscribed in a circle and got π=3. 14, and pointed out that the more sides inscribed in a regular polygon, the more accurate the π value obtained. On the basis of predecessors' achievements, Zu Chongzhi worked hard and calculated repeatedly, and found that π was between 3. 14 15926 and 3. 14 15927. The approximate value in the form of π fraction is obtained as the reduction rate and density rate, where the six decimal places are 3. 14 1929, which is the closest fraction to π value in 1000. How did Zu Chongzhi achieve this result? There's no way to check now. If you imagine that he will solve the problem according to Liu Hui's secant method, you must work out 16384 polygons inscribed in the circle. How much time and labor it takes! This shows that his perseverance and intelligence in academic research are admirable. It has been more than 1000 years since Zu Chongzhi calculated the secret rate and foreign mathematicians got the same result. In order to commemorate Zu Chongzhi's outstanding contribution, some foreign mathematicians suggested that π = be called "ancestral rate".
Zu Chongzhi exhibited famous works at that time and insisted on seeking truth from facts. He compared and analyzed a large number of materials calculated by himself, found serious mistakes in the past calendars, and dared to improve them. At the age of 33, he successfully compiled the Daming Calendar, which opened a new era in calendar history.
Zu Chongzhi and his son Zuxuan (also a famous mathematician in China) solved the calculation of the volume of a sphere with ingenious methods. One principle they adopted at that time was: "If the power supply potential is the same, the products cannot be different." That is to say, two solids located between two parallel planes are cut by any plane parallel to these two planes. If the areas of two sections are always equal, then the volumes of two solids are equal. This principle is called cavalieri principle in western languages, but it was discovered by Karl Marx more than 1000 years after the ancestor. In order to commemorate the great contribution of grandfather and son in discovering this principle, everyone also called this principle "the ancestor principle".
A Self-taught Mathematician —— The Story of Hua
Mathematician Hua dropped out of school when he was a teenager and helped his father run a small cotton shop. In his spare time, he often solves math problems with paper wrapped in cotton.
One day, his father asked him to clean the back room. After cleaning, he went back to the counter and cried, "Where is my arithmetic draft paper?" Dad looked around. Suddenly, he pointed to the back of a person in the distance and said, "I sold my cotton bag to him." Hua caught up with him, bowed, took out his pen and copied the topic on the back of his hand. Passers-by said, "This is really a strange child." Sometimes customers come to buy things, and people ask questions and answer them, which delays business. In the evening, when the shop was closed, he taught himself until late at night. Seeing that he didn't focus on business, his father snatched the book from his hand in a rage and wanted to put it in the stove. It's a good thing his mother got it and it didn't burn.
Once, Hua read a magazine and found that a math paper was wrong. Encouraged by his teacher, he wrote a critical paper and sent it to Shanghai Science Journal, which was published soon. This article changed his path and led him to the palace of mathematics.
Doll doctor-the story of Qin Yuanxun
Qin Yuanxun, a famous mathematician in China, worked hard since childhood. /kloc-entered the famous Shanghai middle school at the age of 0/3 and was on the list. Qin Yuanxun was admitted, but when he got home, he was unhappy. Mom didn't understand, so she asked him, "Why aren't you happy to be admitted?" "I only got more than 70 points in math." Qin Yuanxun cried when he finished speaking. "You have scored more than 90 points in other courses, and your math scores are even lower, but on average, your scores in several courses are not low." "Mathematics is mathematics, how can it be so general?" He is not satisfied with his mother's comfort. At night, Qin Yuanxun lay in bed, tossing and turning, unable to sleep: "I don't believe that mathematics is too abstruse to learn well, so I must learn it well."
From then on, he decided to make a turnaround in mathematics. He often stays up late to do math problems. Sometimes, he has fallen asleep and thought of a solution to the problem. He sat up and wrote down the solution to the problem. During the day, at school, once he encounters a problem, he quickly looks for a teacher and discusses it with him. Qin Yuanxun worked hard for math, and his math scores went up, ranking among the best.
At the age of 24, Qin Yuanxun received a doctorate from Harvard University in the United States, and his classmates affectionately called him "Dr. Doll".