Hello everyone!
I'm having a hard time figuring out how to do this problem.
Any help would be highly appreciated!
Show that U = {(x, y) ∈ Rn : x2 + 4y2 < 4} is open by explicitly finding a ball around each point which is contained in U.
As for what understand, since we have x2 + 4y2 < 4, we can conclude that,
For each (x_0, y_0) contained in U, we have,
((x_0)^2, 4*(y_0)^2) = 4 - epsilon , for some epsilon>0
From there onwards, I would appreciate if I can have any of your help on this.
1 answer