Texts: Consider the function ρ: ℝ^{2} × ℝ^{2} → ℝ
given by ρ (p, q) = √{9 (x_{1} - x_{2})^{2} + 4 (y_{1} - y_{2})^{2}} where p = (x_{1}, y_{1}) and q = (x_{2}, y_{2}) ∈ ℝ^{2}.
a) Show that ρ is a metric.
b) Describe the balls given by the previous metric.
c) Prove that the metric topology given by ρ is equivalent to the usual topology on ℝ^{2}.
d) Compare the metric topology given by ρ with the lexicographic order topology on ℝ^{2}.
Answer the following questions about this literal:
- Which topology is finer, the metric topology or the lexicographic order topology?
- Are they comparable?