Definition of a limit of a function of two variables
if for every there is a such that if is in the domain of and then
Find the limit, if it exists, or show that the limit does not exist
Reminder of the Squeeze Theorem in (which also holds in higher dimensions)
If on an open interval containing (except possibly at ) and if , then
Determine the set of points at which the function is
continuous.
Use polar coordinates to find the limit.