The mathematician's story-ancestor Zu Chongzhi Chongzhi (AD 429-500) was born in Laiyuan County, Hebei Province in the Northern and Southern Dynasties. He read many books on astronomy and mathematics since he was a child, diligently studied and practiced, and finally made him an outstanding mathematician and astronomer in ancient China. Zu Chongzhi's outstanding achievement in mathematics is the calculation of pi. Before Qin and Han Dynasties, people used "diameter", which is the "ancient rate". Later, it was found that the error of ancient rate was too large, and pi should be "the diameter of a circle is one but greater than Wednesday". However, 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 a regular polygon. Liu Hui calculated that the circle is inscribed with 96 polygons, and π = 3.65433. The more accurate the value of π is. 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. He also obtained an approximate value in the form of π fraction as the approximate rate and the secret rate, where the six decimal places are 3.65437. Is the fraction whose denominator is within 1000, which is closest to π. It is impossible to prove how Zu Chongzhi got this result. If he tries to find it according to Liu Hui's "secant" method, he will have to calculate 16384 polygons inscribed in the circle. How much time and energy will it take! It can be seen that his tenacious perseverance and intelligence in academic research are admirable. Zu Chongzhi has calculated the secret rate for more than 1000 years, and foreign mathematicians have 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 and found that there were serious mistakes in the past calendar. At the age of 33, Zu Chongzhi successfully compiled Da Li Ming, which opened a new era in history. Together with his son Zu Xuan (also a famous mathematician in China), he solved the calculation of the volume of a sphere in a clever way. They adopted a principle at that time: "If the power supply potential is the same, the products will not be different." That is, two solids located between two parallel planes are regarded as any plane parallel to these two planes. If the areas of two sections are always equal, the volumes of two solids are also equal. This principle is called cavalieri principle in western languages, but it was discovered by Karl Marx more than 1000 years after Zu's father. In order to commemorate the great contribution of grandfather and son in discovering this principle, everyone also called it the ancestor principle. The mathematician's story-Su 1902 was born in Pingyang County, Zhejiang Province in September. Although the family is poor, his parents scrimp and save, and they have to work hard to pay for his education. When he was in junior high school, he was not interested in mathematics. He thinks mathematics is too simple, and he will understand it as soon as he learns it. It can be measured that a later math class influenced his life. That was when Su was in the third grade. He was studying in No.60 Middle School in Zhejiang Province. Teacher Yang teaches mathematics. He has just returned from studying in Tokyo. In the first class, Mr. Yang didn't talk about math, but told stories. He said: "In today's world, the law of the jungle, the world powers rely on their ships to build guns and gain benefits, and all want to eat and carve up China. The danger of China's national subjugation and extinction is imminent, so we must revitalize science, develop industry and save the nation. Every student here has a responsibility to' rise and fall in the world'. " He quoted and described the great role of mathematics in the development of modern science and technology. The last sentence of this class is: "In order to save the country and survive, we must revitalize science. Mathematics is the pioneer of science. In order to develop science, we must learn math well. "I don't know how many lessons Sue took in her life, but this lesson will never be forgotten. Teacher Yang's class deeply touched him and injected new stimulants into his mind. Reading is not only to get rid of personal difficulties, but to save the suffering people in China; Reading is not only to find a way out for individuals, but to seek a new life for the Chinese nation. That night, Sue tossed and turned and stayed up all night. Under the influence of Teacher Yang, Su's interest shifted from literature to mathematics, and since then, she has set the motto "Never forget to save the country when reading, and never forget to save the country when reading". I am fascinated by mathematics. No matter it is the heat of winter or the snowy night in first frost, Sue only knows reading, thinking, solving problems and calculating, and has worked out tens of thousands of math exercises in four years. Now Wenzhou No.1 Middle School (that is, the provincial No.10 Middle School at that time) still treasures a Su's geometry exercise book, which is written with a brush and has fine workmanship. When I graduated from high school, my grades in all subjects were above 90. /kloc-At the age of 0/7, Su went to Japan to study, and won the first place in Tokyo Technical School, where she studied eagerly. The belief of winning glory for our country drove Su to enter the field of mathematics research earlier. At the same time, he wrote more than 30 papers, and made great achievements in differential geometry. 193 1 obtained the doctor of science degree. Before receiving her doctorate, Su was a lecturer in the Department of Mathematics of Imperial University of Japan. Just as a Japanese university was preparing to hire him as an associate professor with a high salary, Su decided to return to China to teach with his ancestors. After the professor of Zhejiang University returned to Suzhou, his life was very hard. In the face of difficulties, Sue's answer is, "Suffering is nothing, I am willing, because I have chosen a correct road, which is a patriotic and bright road! "This is the patriotism of the older generation of mathematicians.