I was trying to follow the solution my teacher edition gave. I have no idea where the 2 in the denominator came from either. I finally got the solution by adding (Cos30) + (Cos-30) in the denominator.
About 50 years ago, the San Diego Zoo, in California, had the largest gorilla on Earth: its mass was about 3.10 × 102 kg. Suppose a gorilla with this mass hangs from two vines, each of which makes an angle of 30.0° with the vertical. Draw a free-body diagram showing the various forces, and find...
I'm a beginning physics teacher and I like to verify answers and the processes to get to those answers since I am still a bit weak in trig and it has been years since I sat in a physics classroom.