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

CBSE Class 12 Sample Paper for 2020 Boards
CBSE Class 12 Sample Paper for 2020 Boards
Last updated at Dec. 16, 2024 by Teachoo
Transcript
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