
divided chord method
			(better name)




points 

	pa (x=0, y=1) and 

	pb (x=1, y=0)



pa = 90o

pb = 0o




    repeat

	1. locate the point pc on the circle such that the distances pa-pc and pb-pc are equal

	2. determine the angle pca as (paa + pba)/2

		e.g (90 + 0) / 2 = 45o


	3. determine which sub-section the angle in question is located in

		e.g. 78o, range 45o to 90o

			i.e. pc to pa


	4. reset the points pa, pb to be the start and end of this range

	5. repeat this process until a close point to the angle being sought is located


    6. of the angle, sin = y, cos = x, tan = y/x




diagram

to illustrate the method


	circle with radius 1


	lines from 

		x=1, y=0  to  x=0, y=1
		
		x=1, y=0  to  x=0.707, y=0.707

		x=0, y=1  to  x=0.707, y=0.707

	
		points  pa (1, 0)
			pb (0, 1)
			pc (0.707, 0.707)


