Mathematics · 2021
JEE Main · 27 August 2021, Shift 1 · Q63
If the matrix A= (0, 2; K, -1) satisfies A(A^3+3 I)=2 I, then the value of K is:
If the matrix $\displaystyle A=\left(\begin{array}{cc}0 & 2 \\ K & -1\end{array}\right)$ satisfies $\displaystyle A\left(A^3+3 I\right)=2 I$, then the value of $\displaystyle K$ is :
Official answer
(3)
$\displaystyle \frac{1}{2}$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.