Consider the set $F$ of functions from $[0 , 1]$ to $[0 , 1]$ with the metric $(f, g) → sup${$|f(x) − g(x)| x ∈ [0 , 1]$}. Let $C$ denote the collection of constant functions in $F$. Show that $∂C = C$.
To show that $∂C = C$ we have to show $∂C \subseteq C$ and $C \subseteq ∂C$.
I am able to show that $C \subseteq ∂C$ but I am unable to show that $∂C \subseteq C$!!
Please Help... Thank You!!