Open set of real valued functions

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The discussion revolves around proving that the set A = {f ∈ X | f(0) > 1} is open in the metric space (X, d), where d is defined as the supremum distance. It emphasizes that a set is open if every point is an interior point, requiring a neighborhood around each point in A that remains within A. Participants express confusion about identifying the neighborhood of functions in A and determining the interior points. The conversation seeks clarification on how to approach the proof and the characteristics of functions that satisfy the condition f(0) > 1. Understanding these concepts is essential for successfully completing the homework assignment.
rjw5002

Homework Statement


Consider the set X = {f:[0,1] \rightarrow R | f \in C[0,1]} w/ metric d(f,g) = sup|f(x) - g(x)| (x \in [0,1])
Prove that the set A = {f \in X | f(0) > 1} is open in (X,d).



Homework Equations


E is open if every point of E is an interior point
p is an interior point of E if there is a neighborhood N of p s.t. N\subsetE.
C[0,1] is the set of all real valued functions on [0,1]
supremum.

The Attempt at a Solution



To be honest, I have a great deal of difficulty understanding this question. Any hints or advice to help me in the right direction would be greatly appreciated.
 
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