1. The problem statement, all variables and given/known data w=cos(theta) + isin(theta) where 0<theta<pi if the complex number w^2 + (5/w) -2 is purely imaginary, show that 2cos^2 x + 5 cos (theta) -3=0. Hence, find w. 2. Relevant equations cos^2(theta) + sin^2 (theta) = 1 3. The attempt at a solution im guessing to substitue w into the complex number.