Mathematics · 2021
JEE Main · 27 July 2021, Shift 2 · Q82
If A = [1, 1, 1; 0, 1, 1; 0, 0, 1] and M = A + A^2+ A^3+….+ A^20, then the sum of all the elements of the matrix M is equal to \ \ \ \.
If $\displaystyle \mathrm{A}=\left[\begin{array}{lll}1 & 1 & 1 \\ 0 & 1 & 1 \\ 0 & 0 & 1\end{array}\right]$ and $\displaystyle \mathrm{M}=\mathrm{A}+\mathrm{A}^2+\mathrm{A}^3+\ldots .+\mathrm{A}^{20}$, then the sum of all the elements of the matrix M is equal to \_\_\_\_.
Official answer
2020
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.