Mathematics · 2021
JEE Main · 25 February 2021, Shift 2 · Q69
If α, β ∈ R are such that 1-2 i (here i^2=-1 ) is a root of z^2+α z+β=0, then (α-β) is equal to:
If $\displaystyle \alpha, \beta \in \mathbf{R}$ are such that $\displaystyle 1-2 i$ (here $\displaystyle i^2=-1$ ) is a root of $\displaystyle z^2+\alpha z+\beta=0$, then $\displaystyle (\alpha-\beta)$ is equal to:
Official answer
(4)
$\displaystyle -7$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.