Mathematics · 2022
JEE Main · 26 July 2022, Shift 2 · Q30
The number of matrices A= (a, b; c, d), where a, b, c, d ∈{-1,0,1,2,3, ….., 10}, such that A=A^-1, is \ \ \ \.
The number of matrices $\displaystyle A=\left(\begin{array}{ll}a & b \\ c & d\end{array}\right)$, where $\displaystyle a, b, c, d \in\{-1,0,1,2,3, \ldots . ., 10\}$, such that $\displaystyle A=A^{-1}$, is \_\_\_\_.
Official answer
50
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JEE Main 2022 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.