What is the equation for this circle???

Question

There is a circle, perhaps you place 2 points on anywhere on the side of the circle and connect the points with a line, 2 regioins are formed, and when 3 points are placed and all points are connected to each other 4 regions are formed, so on and so forth to different number of points, what equation can be done here????

[IMG]http://i79.photobucket.com/albums/j122/cydave/CIrcle.jpg[/IMG]

http://i79.photobucket.com/albums/j122/cydave/CIrcle.jpg

sorry, the third one is an example of what is exactly the circles

Answer 1

Acro, that equation only works for the first few cases.
I think this is a question from combinatorics, it's been a while. I think a quartic function will work here. Try one of the form R = a*P^4 + b*P^3 + c*P^2 + d*P + e where a,b,c,d,e are constants that you have to find. R is the number of regions and P is the number of points. Try filling out a table for the first 5 cases ie 1,2,3,4 and 5 points. This should give you 5 different equations and should allow you to solve for the unknown constants a,b,c,d and e. Then it should give you valid results for the number of regions .

Answer 2

You cant get an equation for that circle because there are no measurements.

Its like saying (assuming you have no measurents) that you cut a pizza into half, then quarters, then 8ths, then 16ths, etc. etc. What is the equation of this pizza? It doesnt make any sense.

However if you told me the side-length of a slice of pizza was 8 inches I could tell you a lot about that pizza.

Answer 3

???
I don't think I'm quite understanding what you're trying to ask. The equation of a circle with center at coordinates (h, k) and radius r is
(x-h)² + (y-k)² = r²
so any point you draw on it at some coordinate (x, y) will have to satisfy that equality.

Doug

Answer 4

Its impossible to say what the equation is with these data. Sorry

Ana

Answer 5

area is r squared pie circumference is diameter pie d =2 r