Question
For $z=3\left(\cos \frac{\pi}{8}+i \sin \frac{\pi}{8}\right)$ find (i) $z^{4}$, (ii) $z^{-4}$.
Step 1
We can write this in the form $z=r(\cos \theta+i \sin \theta)$ where $r=3$ and $\theta=\frac{\pi}{8}$. Show more…
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