1. The problem statement, all variables and given/known data 4/PI = 2sin(x) - sin(2x) 2. Relevant equations 4/PI = 2sin(x) - sin(2x) 3. The attempt at a solution I have no clue how to do this. This is part of an integration problem for average values. I need to solve for f(c). I know the answer is 1.238, and 2.808.