1. The problem statement, all variables and given/known data In this exercice I'm asked to find out if the limif of the function f(x,y) exists. lim (x,y)→(0,0) sqrt(x*y) / (x^2 - y^2) 2. Relevant equations 3. The attempt at a solution I've tried to approach it from different coordinates (y=x, y=0, x=0, y=sqrt(x),...) but I didn't found any limit... I also tried to prove it didn't exist with the iteration property without luck... Any hint would be highly appreciated. Thanks.