Explain what is meant by a Cauchy sequence, Completeness of a space, and
a Hilbert space (you can assume the definitions of norm, inner product,
and linear space are known).
Prove that the set of continuous functions on the interval \([a,b]\) is complete
with respect to the uniform norm \[ \lVert f\rVert =\max _{x\in [a,b]} |f(x)|. \]