Answer :
|cos2x| = 1/2
|0.999390827019096x| = 1/2
0.9993908270196x = 1/2
0.999390827016 0.999390827016
x = 0.5003047721941
|0.999390827019096x| = 1/2
0.9993908270196x = 1/2
0.999390827016 0.999390827016
x = 0.5003047721941