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Ex 3.4, 2 - Chapter 3 Class 12 Matrices
Last updated at May 29, 2018 by Teachoo
Transcript
Ex3.4, 2 Find the inverse of each of the matrices, if it exists.[ 8(2&1@1&1)] Let A = [ 8(2&1@1&1)] We know that A = IA [ 8(2&1@1&1)] = [ 8(1&0@0&1)] A R1 R1 R2 [ 8( &1 1@1&1)] = [ 8(1 0&0 1@0&1)] A [ 8( &0@1&1)] = [ 8(1& 1@0&1)] A R2 R2 R1 [ 8(1&0@ &1 0)] = [ 8(1& 1@0 1&1 ( 1))] A [ 8(1&0@ &1)] = [ 8(1& 1@ 1&2)] A I = [ 8(1& 1@ 1&2)] A This is similar to I = A-1A Thus, A-1 = [ 8(1& 1@ 1" " &2" " )]
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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.