Mathematics · 2020
JEE Main · 8 January 2020, Shift 1 · Q52
If the equation, x^2+ b x+45=0( b ∈ R ) has conjugate complex roots and they satisfy |z+1|=2 √ 10, then:
If the equation, $\displaystyle x^2+\mathrm{b} x+45=0(\mathrm{~b} \in \mathbf{R})$ has conjugate complex roots and they satisfy $\displaystyle |z+1|=2 \sqrt{10}$, then :
Official answer
(3)
$\displaystyle \mathrm{b}^2-\mathrm{b}=30$
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JEE Main 2020 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.