Solution
= Solution
The numerator is nonzero at $1$ and $-2/3$, so the finite singularities are \b[a <pole> of order three at $1$ and a <pole> of order two at $-2/3$]. The numerator degree exceeds the denominator degree by three, with leading behaviour $z^3/9$. Hence \b[infinity is a <pole> of order three].