3. For any positive integer $n$, let
$I = \oint_C \frac{z^2 + 1}{(z - 1)^n} dz$.
(a) Let $C$ be any circle about $z = 1$, traversed once counterclockwise. Compute $I$ directly by parameterizing $C$.
(b) Let $C$ be any positively-oriented, simple, closed curve enclosing $z = 1$. Compute $I$ by matching it up with Cauchy's integral formula.