The points in the set $\bigg\{z \in C: Arg \bigg(\large\frac{Z-2}{Z-6i}\bigg)-\frac{\pi}{2}\bigg\}$ lie on the curve which is (Where C denotes the set of all complex numbers )

$\begin {array} {1 1} (1)\;circle & \quad (2)\;pair\;of\;lines \\ (3)\;parabola & \quad (4)\;hyperbola \end {array}$

(1) circle
answered Nov 7, 2013 by