1. The problem statement, all variables and given/known data Question 3.b. - http://imgur.com/ztLiRvx 2. Relevant equations For the sake of simplicity, lets assume that lambda = x. 3. The attempt at a solution I tried equating the real an imaginary parts of arctan(1/4). Real: x/2 + 3 = 4. This gives x = 2. Imaginary: x/2 - 3 = 1. This gives x = 8. I'm getting two different values of x(lambda).