Possible Duplicate:
Why is it that $\mathbb{Q}$ cannot be homeomorphic to any complete metric space?
How do you prove that the space of the rational numbers with the usual metric (from the real numbers space) is not complete metrizable?
Possible Duplicate:
Why is it that $\mathbb{Q}$ cannot be homeomorphic to any complete metric space?
How do you prove that the space of the rational numbers with the usual metric (from the real numbers space) is not complete metrizable?