Solution

ID: past-exam-of-the-functional-analysis-and-banach-and-c-algebras-course-of-the-university-of-oxford/2007/a/4/ii/solution

Given a bounded sequence, first pass to a subsequence on which the images under converge. From that subsequence extract another on which the images under converge. Both image sequences, and hence their sum, converge on the latter subsequence. Thus is compact.

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