Given that A is a non-singular matrix of order 3 such that A2 = 2A, then value of |2A| is:

(a) 4             (b) 8 
(c) 64           (d) 16

Ques 28 (MCQ) - Given that A is a non-singular matrix of order 3 such - CBSE Class 12 Sample Paper for 2022 Boards (MCQ Based - for Term 1)

part 2 - Question 28 - CBSE Class 12 Sample Paper for 2022 Boards (MCQ Based - for Term 1) - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards - Class 12
part 3 - Question 28 - CBSE Class 12 Sample Paper for 2022 Boards (MCQ Based - for Term 1) - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards - Class 12

Remove Ads
Teachoo Ā· Class 12 Explore Class 12

Transcript

Question 28 Given that A is a non-singular matrix of order 3 such that A2 = 2A, then value of |2A| is: (a) 4 (b) 8 (c) 64 (d) 16 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 Given that A is a non-singular matrix, ∓ |š‘Ø| = 8 Now, |šŸš‘Ø| = šŸ^šŸ‘ |š‘Ø| = 8 Ɨ 8 = 64 So, the correct answer is (C)

Davneet Singh's photo - Co-founder, Teachoo

Made by

Davneet Singh

Davneet Singh is an IIT Kanpur graduate and has been teaching for 16+ years. At Teachoo, he breaks down Maths, Science and Computer Science into simple steps so students understand concepts deeply and score with confidence.

Many students prefer Teachoo Black for a smooth, ad-free learning experience.