Hi everyone,
I have been recently working on metric spaces, doing some exercises about proving properties, integrability... But there's one I have not idea how to prove it (or maybe I should give an counterexample).
I have to prove if there exists a metric space (X,M,u) such that {u(E) : such that E belongs to M} = [0,+inf]\Q+
If anyone has an idea I would be delighted to read u, thanks in advance.
I have been recently working on metric spaces, doing some exercises about proving properties, integrability... But there's one I have not idea how to prove it (or maybe I should give an counterexample).
I have to prove if there exists a metric space (X,M,u) such that {u(E) : such that E belongs to M} = [0,+inf]\Q+
If anyone has an idea I would be delighted to read u, thanks in advance.