1. The problem statement, all variables and given/known data Find the asymptotic behavior of a quadrupole consisting of a -2 charge at the origin and +1 charges at z = +/- 1. 2. Relevant equations - 3. The attempt at a solution You can construct the Coulomb potentials for these three charges and show that for large r, they all go as 1/r. The problem is that if you add them together, for large r, the -2 cancels the 2*1, so for large r you actually get 0/r. This makes the potential go to zero more quickly than 1/r, and 1/r doesn't seem like a fitting description of the asymptotic behavior. How do I go about incorporating this?