Check sibling questions

Given that A is a square matrix of order 3 and |A| = −4, then adj A| is equal to:

(a) −4     (b) 4
(c) −16   (d) 16

This question is inspired from Question 5 (Choice 2) - CBSE Class 12 Sample Paper for 2021 Boards


Transcript

Question 6 Given that A is a square matrix of order 3 and |A| = −4, then adj A| is equal to: (a) −4 (b) 4 (c) −16 (d) 16 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| = (−4)2 |𝒂𝒅𝒋 𝑨| = 16 So, the correct answer is (d)

  1. Class 12
  2. Solutions of Sample Papers and Past Year Papers - for Class 12 Boards

About the Author

Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science and Computer Science at Teachoo