Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Matrices

Question:

Match List I with List II. "A is a non-singular matrix of order n."

LIST I LIST II
A. $|adj A|$ I. $\frac{1}{|A|}A$
B. $(adj\, A)^{-1}$ II. $2^n|A|$
C. $adj(adj\, A)$ III. $|A|^{n-2}A$
D. $|2A|$ IV. $|A|^{n-1}$

Choose the correct answer from the options given below :

Options:

A-IV, B-II, C-III, D-I

A-IV, B-II, C-III, D-II

A-III, B-II, C-IV, D-I

A-II, B-II, C-III, D-IV

Correct Answer:

A-IV, B-II, C-III, D-II

Explanation:

The correct answer is Option (2) → A-IV, B-II, C-III, D-II

(A) $|adj\, A|=$|A|^{n-1}$ (IV)

(B) $(adj\, A)^{-1}$

$A\,adj\, A=|A|I$

so $(adj\, A)^{-1}=\frac{A}{|A|}$ (I)

(C) $adj(adj\, A)=|A|^{n-2}A$ (III)

(D) $|2A|=2^n|A|$ (II)