Mathematics · 2021
JEE Main · 26 February 2021, Shift 1 · Q73
Let A be a symmetric matrix of order 2 with integer entries. If the sum of the diagonal elements of A^2 is 1, then the possible number of such…
Let A be a symmetric matrix of order $\displaystyle 2$ with integer entries. If the sum of the diagonal elements of $\displaystyle \mathrm{A}^2$ is $\displaystyle 1$ , then the possible number of such matrices is :
Official answer
(2)
$\displaystyle 4$
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