Complex Taylor and Laurent expansions

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Let $f(z):=\dfrac{1}{2-z-z^2}, z\in\mathbb{C}\setminus\left\{ {1, -2}\right\}$.

i) Express $f$ in the form $\dfrac{A}{1-z}+\dfrac{B}{2+z}$. [Answer to this is $\dfrac{1/3}{1-z}+\dfrac{1/3}{2+z}$].

ii) Write down the Taylor expansion of $f$ on the disk $|z|<1$.

iii) Write down the Laurent expansion of $f$ on the annulus $1<|z|<2$.

Not sure of what to do here. I assume Laurent's Theorem is useful.

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I'll solve $\text{(iii)}$ after which you should be able to handle $\text{(ii)}$.

Let $z\in \mathbb C\setminus \{-2, 0, 1\}$.

The following holds:

$$\dfrac{1}{1-z}=-\dfrac 1 z\dfrac{1}{1-\frac 1 z}=-\dfrac 1 z\sum \limits _{n=0}^\infty\left(\left(\dfrac 1 z\right)^n\right)= \sum \limits _{n=0}^\infty\left(-\left(\dfrac 1 z\right)^{n+1}\right), \text{ if }\underbrace{\left|\dfrac 1 z\right|<1}_{\iff \large{1<|z|}},$$

$$\dfrac 1{2+z}=\dfrac 1 2\dfrac 1{1-\left(-\frac z 2\right)}=\dfrac 1 2\sum \limits _{n=0}^\infty\left(\left(-\dfrac z 2\right)^n\right)=\sum \limits _{n=0}^\infty\left(\dfrac {(-1)^n}{2^{n+1}}z^n\right), \text{ if }\underbrace{\left|\dfrac z 2\right|<1}_{\iff \large{|z|<2}}.$$

Factoring in $\dfrac 1 3$ and adding you get the laurent series in the set $\{z\in \mathbb C\colon 1<|z|\}\cap \{z\in \mathbb C\colon |z|<2\}$, that is, you get the laurent series in the annulus $1<|z|<2$.