Mathematics · 2020
JEE Main · 8 January 2020, Shift 2 · Q54
If A = (2, 2; 9, 4) and I = (1, 0; 0, 1), then 10 A^-1 is equal to:
If $\displaystyle \mathrm{A}=\left(\begin{array}{ll}2 & 2 \\ 9 & 4\end{array}\right)$ and $\displaystyle \mathrm{I}=\left(\begin{array}{ll}1 & 0 \\ 0 & 1\end{array}\right)$, then $\displaystyle 10 \mathrm{~A}^{-1}$ is equal to :
Official answer
(4)
$\displaystyle A-6 I$
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JEE Main 2020 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.