Mathematics · 2021
JEE Main · 18 March 2021, Shift 1 · Q62
If the equation a |z|^2+ᾱ̅z̅+̅α̅z̄̅+ d =0 represents a circle where a, d are real constants, then which of the following condition is correct?
If the equation $\displaystyle \mathrm{a}|z|^2+\overline{\bar{\alpha} z+\alpha \bar{z}}+\mathrm{d}=0$ represents a circle where a, d are real constants, then which of the following condition is correct ?
Official answer
(2)
$\displaystyle |\alpha|^2-a d>0 \text { and } a \in \mathbf{R}-\{0\}$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.