Question:
If the equation $a|z|^{2}+\overline{\bar{\alpha} z+\alpha \bar{z}}+d=0$ represents a circle where a,d are real constants then which of the following condition is correct?
Correct Option: , 2
Solution:
az $\bar{z}+\alpha \bar{z}+\bar{\alpha} z+d=0 \rightarrow$ Circle
centre $=\frac{-\alpha}{a} \quad 2=\sqrt{\frac{\alpha \bar{\alpha}}{a^{2}}-\frac{d}{a}}=\sqrt{\frac{\alpha \bar{\alpha}-a d}{a^{2}}}$
So $|\alpha|^{2}-\mathrm{ad}>0 \& \mathrm{a} \in \mathrm{R}-\{0\}$