In: Advanced Math
Given the set A = {(x, y) ∈ R2 | x2 + y2 < 1 and y ≥ 0}. Draw sketches of cl A, int A, ∂A, (cl(Ac))c, the limit points of A, and the isolated points of A. Try to be clear about what the sketch is describing. (The answer does not depend on whether one uses the Euclidean distance or the taxi distance on R2.)