cos θ = -
/ 6
sin θ =
sin θ =
sin θ = 2/
tan β = 5/12
sin β = 5/5
cos β = 12/5
sin ( θ + β ) = sin θ cos β + cos θ sin β
sin ( θ + β ) = 2/
* 12/5 + ( -
/ 6 ) * 5/5
sin ( θ + β ) = 2/2.44 * 2.4 + 1.414/6 * 1
sin ( θ + β ) = 0.8196 * 2.4 + 0.2356 * 1
sin ( θ + β ) = 1.96 + 0.2356
sin ( θ + β ) = 2.1956