Ex 4.5, 18 - Class 12
Last updated at May 29, 2018 by Teachoo
Transcript
Ex 4.5, 18 If A is an invertible matrix of order 2, then det(A−1) is equal to A. det (A) B. 1det (A) C. 1 D. 0 We know that AA-1 = I Taking determinant both sides AA−1= |I| |A| |A-1| = |I| |A| |A-1| = 1 |A-1| = 1|A| Since |A| ≠ 0 Hence, |A-1| = 1|A| is valid Thus, the correct answer is B
Chapter 4 Class 12 Determinants
Serial order wise
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Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 8 years. He provides courses for Maths and Science at Teachoo. You can check his NCERT Solutions from Class 6 to 12.
