1. The problem statement, all variables and given/known data 2. Relevant equations trigonometric identities 3. The attempt at a solution I did a trig substitution of u=tan(θ/2) and from that I could substitute cos(θ) = 1-u2/1+u2 dθ = 2/(1+u2) du = 1/2 sec2(θ/2) dθ I simplified a bit and changed the bounds to get 2du/(5u2 + 1)(1 + u2)2 with lower bound 0 and upper bound 1. I think at this point I have to do partial fractions. Do I need 3 linear terms or 2? I tried Ax+B/5u2+1 + Cx + D/(1+u2)2 + Ex+F/(1+u2) = 2/(5u2 + 1)(1 + u2) I have no idea how to evaluate such a complicated system of equations. I could really use some guidance here.