4.5 Show that the norm || . || on C[0,2] does not come from an inner product. Hint: show that the norm || . || does not satisfy the parallelogram law, e.g., for f(x) = = {2- if x = [0,1], if x = [1,2], 1 X if x = [0,1], g(x) = X - 1 if x = [1,2]. The function f is a so-called B-spline, see Chapter 10.