CBSE Class 12 Sample Paper for 2021 Boards

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Question 20 (Choice 1) - CBSE Class 12 Sample Paper for 2021 Boards - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards

Last updated at August 10, 2026 by

If A is a square matrix of order 3 such that š“ 2 = 2š“, then find the value of |A|.

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If A is a square matrix of order 3 such that A^2 = 2A, then find

Question 20 (Choice 1) - CBSE Class 12 Sample Paper for 2021 Boards - Part 2

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Question 20 (Choice 1) If A is a square matrix of order 3 such that š“2 = 2š“, then find the value of |A|. Given A2 = 2A Taking Determinant both sides |š‘Ø^šŸ | = |2š“| |š‘Ø Ɨ š‘Ø| = |2š“| |š“||š“| = |šŸš‘Ø| Since order of matrix is 3, using|š‘˜š“|=š‘˜^š‘› |š“| |š“||š“| = šŸ^šŸ‘ |š‘Ø| |š“||š“| = 8|š“| |š“||š“| āˆ’ 8|š“| = 0 |š“| (|š“|āˆ’"8" ) = 0 Thus, |š‘Ø| = 0 or |š‘Ø| = 8

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