Paper 3, Section I, H

Topics in Analysis
Part II, 2020

State Runge's theorem about the uniform approximation of holomorphic functions by polynomials.

Explicitly construct, with a brief justification, a sequence of polynomials which converges uniformly to 1/z1 / z on the semicircle {z:z=1,Re(z)0}\{z:|z|=1, \operatorname{Re}(z) \leqslant 0\}.

Does there exist a sequence of polynomials converging uniformly to 1/z1 / z on {z:z=1,z1}\{z:|z|=1, z \neq 1\} ? Give a justification.