The amplitude of $0$ is

$x$ and $y$ are two complex numbers such that $|x|=|y|=1$. If $\operatorname{Arg}(x)=2 \alpha$,$\operatorname{Arg}(y)=3 \beta$,and $\alpha+\beta=\frac{\pi}{36}$,then $x^6 y^4+\frac{1}{x^6 y^4}=$

If $z_1 = -\sqrt{3} + i$ and $z_2 = -\sqrt{3} - i$,then the principal amplitude of the complex number $\frac{z_1}{z_2}$ is

Convert the following complex number into polar form: $\frac{1+7i}{(2-i)^2}$

If $z = \sqrt{2} \sqrt{1 + \sqrt{3} i}$ represents a point $P$ in the Argand plane and $P$ lies in the third quadrant,then the polar form of $z$ is

If $arg(z) < 0$,then $arg(-z) - arg(z)$ equals