Solution
ID: past-exam-of-the-mathematics-course-of-the-university-of-cambridge/2009/ii/paper-3/12f/a/solution
Past exam of the mathematics course of the University of Cambridge 2009 ii Paper 3 12F a Solution by
Codex 0 Created 2026-09-24 Updated 2026-10-14
The polynomial form of the Runge approximation theorem says: if is compact, is connected, and is holomorphic on a neighborhood of , then for every there is a polynomial with . Choosing errors tending to zero gives a uniformly convergent sequence of polynomials. Equivalently, on an open domain with connected complement in the Riemann sphere, every holomorphic function is the compact-uniform limit of polynomials. The connected-complement hypothesis excludes enclosed holes containing poles of the function being approximated.
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