If $\frac{3+i \sin \theta}{4-i \cos \theta}, \theta \in[0,2 \pi],$ is a real number, then an argument of $\sin \theta+\mathrm{i} \cos \theta$ is
$-\tan ^{-1}\left(\frac{3}{4}\right)$
$\tan ^{-1}\left(\frac{4}{3}\right)$
$\pi-\tan ^{-1}\left(\frac{4}{3}\right)$
$\pi-\tan ^{-1}\left(\frac{3}{4}\right)$
The argument of the complex number $\frac{{13 - 5i}}{{4 - 9i}}$is
If $z = \cos \frac{\pi }{6} + i\sin \frac{\pi }{6}$ then
Let $z$ be a complex number (not lying on $X$-axis) of maximum modulus such that $\left| {z + \frac{1}{z}} \right| = 1$. Then
If $z$ is a complex number, then $(\overline {{z^{ - 1}}} )(\overline z ) = $
$z_1$ and $z_2$ are two complex numbers such that $|z_1 + z_2|$ = $1$ and $\left| {z_1^2 + z_2^2} \right|$ = $25$ , then minimum value of $\left| {z_1^3 + z_2^3} \right|$ is