Let \(f_n\in C([0,1])\) for \(n=1,2,\ldots \). Show that the following statements are equivalent:
(a) For every \(\lambda \in C([0,1])^*\) we have \(\lambda (f_n)\to 0\) as \(n\to \infty \).
(b) \(f_n(x)\to 0\) for every \(x\in [0,1]\) and \(\sup \lVert f_n\rVert _\infty <\infty \).
Here \(\lVert f\rVert _\infty =\sup _{x\in [0,1]}|f(x)|\).