Mathematics · 2025
JEE Main · 29 January 2025, Shift 2 · Q4
Let A =[ a_i j] be a matrix of order 3 × 3, with a_i j=(√ 2 )^i+j. If the sum of all the elements in the third row of A^2 is α+β √ 2, α, β ∈ Z, then…
Let $\displaystyle \mathrm{A}=\left[\mathrm{a}_{i j}\right]$ be a matrix of order $\displaystyle 3 \times 3$, with $\displaystyle \mathrm{a}_{i j}=(\sqrt{2})^{i+j}$. If the sum of all the elements in the third row of $\displaystyle \mathrm{A}^2$ is $\displaystyle \alpha+\beta \sqrt{2}, \alpha, \beta \in \mathbf{Z}$, then $\displaystyle \alpha+\beta$ is equal to :
Official answer
From NTA’s final answer key for this paper.
(3)
$\displaystyle 224$
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JEE Main 2025 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.