Multivariable Limit Problem

I am having some problems with the following problems:

1.

Using l'Hôpital's rule I got that the limit equals.

2.

I am not really sure how to proceed here. I mean, I could approach along the y axis, then am I able to use l'Hôpital's rule?Also, if I approach along y = x afterward I believe I would get 2 for the limit, whereas along the y-axis would yield 1 provided I could use l'Hôpital's rule. In that case the limit would not exist.

3.

On this one I don't really know what to do.