4.216/2 = 2.108
sin 60 equals opposite side over hypotenuse
opposite side = 2.108
hypotenuse = r (the radius of the circle)
sin 60 = 2.108/r
diameter = 2r
Draw a triangle with 120, 30, and 30 degree angles. The longest leg is length 4.216.
Bisect the longest leg and the 120 degree angle.
You now have a triangle with a 90, 60 and 30 degree angles and a leg opposite the 60 degree angle has length 2.108.
sin 60 equals 2.108/r. r is the radius.
r equals 2.108/sin 60. sin 60 equals .866
r, the radius (the hypotenuse) = 2.434
twice the radius equals the diameter.
2r = 4.868
cos x = adjacent side over hypotenuse
sin x = opposite side over hypotenuse
tan x = opposite side over adjacent side
John
