1. The problem statement, all variables and given/known data Prove the statement 3. The attempt at a solution I am clueless as to how I would go about doing this, I know the basic properties. I think it has to do with using epsilon somewhere and taking the limit as epsilon approaches zero, as shown here: http://www-thphys.physics.ox.ac.uk/people/JohnMagorrian/mm/dirac.pdf but I really have no idea how they're using it. The prof did something similar in class but he used -epsilon to epsilon in the limits of integration to show that the integral of δ(x)f(x) is just f(0). Pretty mysterious to me, any help is greatly appreciated.