What is the Closest Point to a Compact Set in a Metric Space?

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Homework Statement



Let X be a metric space and let K be any non-empty compact subset of X, and let x be an element of X. Prove that there is a point y is an element of K st d(x,y) leq d(x,k) for every k an element of K.

Homework Equations



triangle inequality


The Attempt at a Solution



i tried proof by contradiction with the triangle inequality, and it didn't get me anywhere
 
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Look at the set {d(x,k) : k in K}. Note in particular that it's bounded below.
 
its bounded below as k gets closer to x is that inf K?