For thousands of years, countless famous mathematicians have devoted their lives to the study of pi. As an English mathematician said, "This wonderful 3. 14 159 slipped into every door, rushed into every window and got into every chimney." The whole study of π can be divided into four stages:
The first stage: the early research stage of π value. Representative figures are Archimedes, an ancient Greek mathematician, Liu Hui and Zu Chongzhi, great mathematicians in China. Archimedes was the first person in the world to calculate pi. So pi is expressed by the first letter "π" of the Greek word "circumference".
Pi, which was first used in China, was 3, and it was used until the Han Dynasty. Liu Hui, a mathematician in the Han Dynasty, further refined pi to 3. 14 16. Zu Chongzhi, a mathematician in the Northern and Southern Dynasties, calculated that the value of π was between 3. 14 15926 and 3. 14 15927. Sum was used as the approximation of π for the first time, and the error was less than 0.00000 1.
The second stage: using secant to find π value. 1427, the Arab mathematician Al Cassie calculated the π value to 16 after the decimal point. 1573, Otto got a value similar to that calculated by Zu Chongzhi, with a difference of more than 1000 years, so the world called pi "ancestral rate".
1596, the German mathematician Rudolph tried to find the π value with 35 decimal places. 1630, the German mathematician Bergen created the highest record of finding π value with the method of secant circle-39 decimal places.
The third stage: the stage of finding π value by analytical method. 1699, the British mathematician Sharp got 7 1 decimal places. 1706, the British mathematician Machin found 100 digits after the decimal point.
1844, German mathematician osawa reached 200 decimal places. 1947, American mathematician Ferguson discovered 7 10 decimal places. 1949, American mathematician Renzi cooperated with Smith and got 1 120, which created the highest record of finding π value by "analytical method".
The fourth stage: the stage of finding π value by computer. 1949, Mermid in the United States was the first person in the world to calculate pi with an electron tube computer. He calculated the value of π to 2037 decimal places.
196 1 year, American mathematician Long Qi calculated to 100265 digits after the decimal point with an electronic computer. At this point, the computer can calculate the value of π to 65438+ million decimal places in only 8 hours and 43 minutes. 1973, the French mathematician Giraud worked out 1 decimal. If this amazing number is printed, it will be a book with more than 300 pages.
1987, Japanese mathematician Yasunari Kanda (also translated as Yasunari Kanda) got134,217728 decimal places. 1990 has exceeded the decimal mark of 10 billion. If printed into a book, it will reach three or four million pages.