Mathematics · 2017
JEE Main · 8 April 2017, Shift 1 · Q65
Let A be any 3 × 3 invertible matrix. Then which one of the following is not always true?
Let A be any $\displaystyle 3$ × $\displaystyle 3$ invertible matrix. Then which one of the following is not always true ?
Official answer
(4)
$\displaystyle \operatorname{adj}(\operatorname{adj}(\mathrm{A}))=|\mathrm{A}| \cdot(\operatorname{adj}(\mathrm{A}))^{-1}$
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JEE Main 2017 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.