If $z_1$ and $z_2$ are two unimodular complex numbers that satisfy $z_1^2 + z_2^2 = 5,$ then ${\left( {{z_1} - {{\bar z}_1}} \right)^2} + {\left( {{z_2} - {{\bar z}_2}} \right)^2}$ is equal to -
$6$
$5$
$9$
$10$
If $z$ is a complex number such that $\frac{{z - 1}}{{z + 1}}$ is purely imaginary, then
If complex numbers $z_1$, $z_2$ are such that $\left| {{z_1}} \right| = \sqrt 2 ,\left| {{z_2}} \right| = \sqrt 3$ and $\left| {{z_1} + {z_2}} \right| = \sqrt {5 - 2\sqrt 3 }$, then the value of $|Arg z_1 -Arg z_2|$ is
The conjugate of the complex number $\frac{{2 + 5i}}{{4 - 3i}}$ is
If $|{z_1} + {z_2}| = |{z_1} - {z_2}|$, then the difference in the amplitudes of ${z_1}$ and ${z_2}$ is
Given $z$ is a complex number such that $|z| < 2,$ then the maximum value of $|iz + 6 -8i|$ is equal to-