I am having a little difficulty understanding Mathematica's output regarding a specific limit. My function is f(x,y)=(x^2+4xy+y^2)/(x^2+xy+y^2) and I am taking the limit as (x,y) approaches (0,0). I am not asking for an answer. This limit does not exist because if we let y approach along y = x we get a limit of 2 and if we let y approach along y = -x we get a limit of -2. However, when I do this limit in Mathematica, I got an answer of 1. Why doesn't Mathematica recognize that this limit does not exist?