Damn danang is right about autocad draws it wrong!
Autocad could not overlapped the circle and a line has value of R.
First I draw a circle has radius of 1 000 000 000
Then splitted one of its quarter to two equal part by using a line has same radius as 1 000 000 000
Until now, everything is okay. In this point, we have to check the intersection point about, is danang right or not. So we are zooimg the intersection:
Shit. Our line has 1 000 000 000 units is longer than radius has theorically 1 000 000 000. But as far as we see, circle is actually less than 1 000 000 000. There is some missing areas here. My job is harder now. Because this circle never will be perfect. Even so I'll done the working by considering the missing area.
This proves pi is actually bigger than calculated. But how much? We can make an estimation about it as comparing the lenghts by shrinking our line:
This is the ratio:
999871538 / 1000000000 % mistake. But we will calculate pi depends on square of R. So we have to multipy it by itself. Then it turns to:
0,999871538^2= 0, 99974309.
If same mistake continues during all circle, pi turns to:
3.14159265359/0,99974309= 3,1424
This is an estimation value related whether if same mistake continues. We'll do better estimation even at the end of this working by correcting all values right this way.