Points #(2 ,4 )# and #(4 ,9 )# are #(3 pi)/4 # radians apart on a circle. What is the shortest arc length between the points?

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Answer 1 · 2018-02-04T05:54:41

Shortest Arc length #s = r * theta = color(green)(6.8669#

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Chord #c = sqrt((4-2)^2 + (9-4)^2) = 5.3852#

radius #r = c / (2 sin (theta/2)) = 5.3852 / (2 * sin ((3pi)/8) = 2.9144#

Shortest Arc length #s = r * theta = 2.9144 * ((3pi)/4) = color(green)(6.8669#