**HOW DO YOU MAKE PI?**

**Pi is the ratio of the
circumference of a circle to it's diameter .**

**To seven places pi is
3.1415927.**

**You find pi by approximating
the length around a circle with the**

**length around an inscribed
regular polygon then divide this by the circle diameter.**

**By summing the lengths
of the sides of a regular polygon that is inscribed**

**within a circle you approximate
the circumference of a circle.**

**The more sides on a polygon
the closer you come to the true circumference**

**of a circle.**

**EXAMPLE:**

**Let us start with a circle
of radius R=1. Inscribe within this circle a regular**

**polygon having N=6 sides.**

**Using trigonometry we
get formula (2) below. This along with formula (3)**

**Will give an approximate
circumference of 6x2x1xsin(180/6)=6.**

**Using the traditional
formula(1) for circumference gives**

**2x1x3.141592=6.283184.**

**If the polygon had more
sides the answer would be more accurate.**

**We arrive at formula
(4) to give the circumference of a circle.**

**If we set equal formula
(1) and (4) then factors 2xR cancel out**

**giveing Pi equal to
formula (5).**

**Using formula (5) you
get pi=3.1407433 for a polygon of 78 sides.**

**For 1303 sides you get
Pi=3.1415897. With 45000 sides pi**

**is calculated as 3.1415927.**