- #1
Ankit Mishra
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Homework Statement
Let (X, d) be a metric space. The set Y in X , d(x; y) less than equal to r is called a closed set with radius r centred at point X.
Show that a closed ball is a closed set.
Homework Equations
In a topological space, a set is closed if and only if it coincides with its closure. Equivalently, a set is closed if and only if it contains all of its limit points.
The Attempt at a Solution
I have no idea, please help!