If \((x_n)\) is a weakly convergent sequence in a normed space \(X\), say, \(x_n\to x_0\) weakly, show that there is a sequence \((y_n)\) of linear combinations of elements of \((x_n)\) which converges strongly to \(x_0\). Hint: First prove that \(x_0\in \overline {\operatorname {span}(x_n)}\).
Question
Math 6420 • PDE
Spring 2017 • Question 1