If $|z - 25i| \le 15$, then $|\max .amp(z) - \min .amp(z)| = $
${\cos ^{ - 1}}\left( {\frac{3}{5}} \right)$
$\pi - 2{\cos ^{ - 1}}\left( {\frac{3}{5}} \right)$
$\frac{\pi }{2} + {\cos ^{ - 1}}\left( {\frac{3}{5}} \right)$
${\sin ^{ - 1}}\left( {\frac{3}{5}} \right) - {\cos ^{ - 1}}\left( {\frac{3}{5}} \right)$
If $|z|\, = 1$ and $\omega = \frac{{z - 1}}{{z + 1}}$ (where $z \ne - 1)$, then ${\mathop{\rm Re}\nolimits} (\omega )$ is
If $z$ is a complex number, then $(\overline {{z^{ - 1}}} )(\overline z ) = $
If complex number $z = x + iy$ is taken such that the amplitude of fraction $\frac{{z - 1}}{{z + 1}}$ is always $\frac{\pi }{4}$, then
Find the complex number z satisfying the equations $\left| {\frac{{z - 12}}{{z - 8i}}} \right| = \frac{5}{3},\left| {\frac{{z - 4}}{{z - 8}}} \right| = 1$
If $z$ is a complex number such that $\left| z \right| \ge 2$ , then the minimum value of $\left| {z + \frac{1}{2}} \right|$: