If $z_1 , z_2$ and $z_3, z_4$ are $2$ pairs of complex conjugate numbers, then $\arg \left( {\frac{{{z_1}}}{{{z_4}}}} \right) + \arg \left( {\frac{{{z_2}}}{{{z_3}}}} \right)$ equals
$0$
$\frac{\pi}{2}$
$\frac{3\pi}{2}$
$\pi $
Given $z$ is a complex number such that $|z| < 2,$ then the maximum value of $|iz + 6 -8i|$ is equal to-
Let $A =\left\{\theta \in(0,2 \pi): \frac{1+2 i \sin \theta}{1- i \sin \theta}\right.$ is purely imaginary $\}$. Then the sum of the elements in $A$ is
Let $S=\left\{z \in C : z^{2}+\bar{z}=0\right\}$. Then $\sum \limits_{z \in S}(\operatorname{Re}(z)+\operatorname{Im}(z))$ is equal to$......$
The argument of the complex number $\frac{{13 - 5i}}{{4 - 9i}}$is
If $z = 3 + 5i,\,\,{\rm{then }}\,{z^3} + \bar z + 198 = $