Complex Analysis: Theory and Applications · Problem 4.3.1

Elementary Functions — Howell & Matthews

Mathematics — Complex Analysis · series-evaluation-convergence

Problem

Evaluate ((a))

\displaystyle\sum_{n=0}^{\infty} \frac{(1+i)^n}{2^n}

. ((b))

\displaystyle\sum_{n=0}^{\infty} \left(\frac{1}{2+i}\right)^n