CBSE Class 12 Sample Paper for 2022 Boards (MCQ Based - for Term 1)
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CBSE Class 12 Sample Paper for 2022 Boards (MCQ Based - for Term 1)
Last updated at December 16, 2024 by Teachoo
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 |šØ^š | = |2š“| |šØ Ć šØ| = |2š“| |š“||š“| = |ššØ| Since order of matrix is 3, using|šš“|=š^š |š“| |š“||š“| = š^š |šØ| |š“||š“| = 8|š“| |š“||š“| ā 8|š“| = 0 |š“| (|š“|ā"8" ) = 0 Thus, |šØ| = 0 or |šØ| = 8 Given that A is a non-singular matrix, ā“ |šØ| = 8 Now, |ššØ| = š^š |šØ| = 8 Ć 8 = 64 So, the correct answer is (C)
