Powers and roots of complex numbers

2010004616

Level: 
A
Let \( z \in \mathbb{C}\). The value of the argument of \(z^6\) is \(270^{\circ}\) and \(|z|^6=27\). Find \(z\).
\( z=\frac{\sqrt{6}}{2}(1+\mathrm{i})\)
\( z=\frac{\sqrt{6}}{2}(1-\mathrm{i})\)
\( z=\sqrt{3}\mathrm{i}\)
\( z=3(\cos 45^{\circ} + \mathrm{i} \sin 45^{\circ})\)

2010004617

Level: 
A
Let \( z \in \mathbb{C}\). The value of the argument of \(z^5\) is \(300^{\circ}\) and \(|z|^5=\frac1{32}\). Find \(z\).
\( z=\frac{1}{4}(1+\mathrm{i}\sqrt{3})\)
\( z=\frac{1}{4}(1-\mathrm{i}\sqrt{3})\)
\( z=-\frac{1}{2}\mathrm{i}\)
\( z=\frac{1}{2}(\cos 60^{\circ} - \mathrm{i} \sin 60^{\circ})\)