Mathematics · 2019
JEE Main · 12 January 2019, Shift 1 · Q62
If (z -α)/(z +α)(α ∈ R ) is a purely imaginary number and | z |=2, then a value of α is:
If $\displaystyle \frac{\mathrm{z}-\alpha}{\mathrm{z}+\alpha}(\alpha \in \mathbf{R})$ is a purely imaginary number and $\displaystyle |\mathrm{z}|=2$, then a value of $\displaystyle \alpha$ is :
Official answer
(2)
$\displaystyle 2$
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JEE Main 2019 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.