Mathematics · 2021
JEE Main · 16 March 2021, Shift 1 · Q88
The total number of 3 × 3 matrices A having entries from the set {0, 1, 2, 3} such that the sum of all the diagonal entries of AA^T is 9, is equal to…
The total number of $\displaystyle 3 \times 3$ matrices A having entries from the set {$\displaystyle 0$, $\displaystyle 1$, $\displaystyle 2$, $\displaystyle 3$} such that the sum of all the diagonal entries of $\displaystyle \mathrm{AA}^{\mathrm{T}}$ is $\displaystyle 9$, is equal to \_\_\_\_.
Official answer
766
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