A <removable singularity> at $a$ means that there is a <holomorphic function> on the whole disc which agrees with $f$ away from $a$. Equivalently, the <Laurent series> has no negative powers. The value at $a$ is filled in by its finite limit.

Solution

Past exam of the algebra, analysis and differential equations 1 course of the University of Oxford / 2004 / Analysis / 5 / a / Solution

 Solution (source code)