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Mathematics · 2025 · 1 mark
CBSE 2025 · Region 4 · Set 1 · Q7
If M and N are square matrices of order 3 such that det ( M )= m and MN = mI, then det ( N ) is equal to:
If M and N are square matrices of order $\displaystyle 3$ such that $\displaystyle \operatorname{det}(\mathrm{M})=\mathrm{m}$ and $\displaystyle \mathrm{MN}=\mathrm{mI}$, then $\displaystyle \operatorname{det}(\mathrm{N})$ is equal to :
Official answer
(D)
$\displaystyle \mathrm{m}^{2}$
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CBSE Class 12 Mathematics past-paper question from the 2025 board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.