Points (5 ,2 ) and (1 ,4 ) are (2 pi)/3 radians apart on a circle. What is the shortest arc length between the points?

1 Answer
Jan 7, 2018

Shortest arc length s = color (blue)5.4077

Explanation:

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Chord length l_c = sqrt((1-5)^2 + (4-2)^2) = 4.4721

r = l_c / 2sin(theta/2) = 4.4721/(2*sin (pi/3)) = 2.582

Arc length s = r theta = 2.582 * ((2pi)/3) = color (blue)(5.4077)