How to prove for example that ?
I want to learn it. I've been looking for some notes that show how to prove multivariable limits by the epsilon-delta definition, but not succeed.
As a sidenote... : you're currently working on
Since we're in finite dimension, all the norms are equivalent.
So you can choose whatever norm you want :
norm 1 :
norm 2 :
and by noting (a,b)-(c,d)=(a-c,b-d)
maybe the norm 1 would be easier to manipulate