CBSE Class 12 Sample Paper for 2020 Boards

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Maths Class 12
Solutions of Sample Papers and Past Year Papers - for Class 12 Boards

Question 1 - CBSE Class 12 Sample Paper for 2020 Boards - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards

Last updated at August 14, 2026 by

If A is any square matrix of order 3 × 3 such that |A| = 3, then the value of |adj A| is ? 

(a) 3         (b) 1/3  (c) 9           (d) 27

If A is square matrix of order 3 x 3 such that |A| = 3, then |adj A|

Question 1 - CBSE Class 12 Sample Paper for 2020 Boards - Part 2

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Question 1 If A is any square matrix of order 3 × 3 such that |𝐴| = 3, then the value of |𝑎𝑑𝑗 𝐴| is ? (a) 3 (b) 1/3 (c) 9 (d) 27 We know that |𝑎𝑑𝑗 𝐴| = |A|^(𝑛−1) where n is the order of determinant Given Order = n = 3 So, |𝑎𝑑𝑗 𝐴| = |A|^(3−1) |𝑎𝑑𝑗 𝐴| = |A|^2 |𝑎𝑑𝑗 𝐴| = 32, |𝒂𝒅𝒋 𝑨| = 9 So, correct answer is (c) - 9 1 mark

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