
Robert J. answered 05/13/13
Tutor
4.6
(13)
Certified High School AP Calculus and Physics Teacher
Take reciprocals,
sin2(x/2) = cos(x)/2
=> 2sin2(x/2) = cos(x)
=> 1-cos(x) = cos(x)
=> cos(x) = 1/2
=> x = pi/3, 5pi/3 on [0, 2pi).