History of pi

Pi has been known for four thousand years, and even nowadays mathmatians can only present the approximate value of pi, today, I would like to introduce a brief story of pi to you! Ready?

1. The Babylonians calculated the area of a circle by taking 3 times the square of its radius, and gave pi the value of 3. 

2, the first calculation was done by Archimedes of Syracuse, one of the greatest mathematicians of the ancient world. He knew that he had only found the approximation of pi's value, but he showed that pi is between 3 1/7 and 3 10/71

3. Zu chongzhi, a brilliant Chinese mathematician calculated the value of the ratio of the circumference of a circle to its diameter to be 335/113. 

4. Mathematicians began to use the symbol in the 1700s

Have you learnt anything from this intro?

Next time, when you are enjoying a slice of Apple pie, think about 3.1415...