Throughout history, many studies have been done about the number of pi (), which is the anchor part of the circumference of the circle. Some of them even went forward and appointed a blessing to the pi () number or even trying to give various secrecy. Nowadays; people from the date of birth to the number of people in the population reported that they include every number and even prepared internet sites. However, there are almost every irrational number of cases. So almost every irrational number contains numbers of this type. The most important reason for attributing sanctity to the number of pi () is that much academic work is done on it. The history of pi () is known as BC. It goes back to 2550. But it was the first time that John Wallis (1616-1703, England) identified the number without error, and later, many pi () numbers were found. Rational numbers, such as the ladder method, limit, serial, integral using the concepts such as the number of pi () studies have been done. Their number is around two hundred. In this study, we have obtained four equations that find pi () number.  

Keywords - Pi () number, degree, grad, trigonometry, limit

[1] http://www.ilkkimbuldu.com/pi-sayisi
[2] http://www.ibrahimay.net/bilim/ahmes-misir-mo-1680-mo-1620-verhind-papirusu
[3] https://onedio.com/haber/3-14-pi-gununde-pi-sayisi-hakkindabilmeniz-gereken-16-sey-268718