Mathematics · 2025
JEE Main · 29 January 2025, Shift 2 · Q9
Let A =[ a_i j] be a 2 × 2 matrix such that a_i j ∈{0,1} for all i and j. Let the random variable X denote the possible values of the determinant of…
Let $\displaystyle \mathrm{A}=\left[\mathrm{a}_{i j}\right]$ be a $\displaystyle 2 \times 2$ matrix such that $\displaystyle \mathrm{a}_{i j} \in\{0,1\}$ for all $\displaystyle i$ and $\displaystyle j$. Let the random variable X denote the possible values of the determinant of the matrix A. Then, the variance of X is :
Official answer
From NTA’s final answer key for this paper.
(4)
$\displaystyle \frac{3}{8}$
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JEE Main 2025 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.