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Ex 3.3
Ex 3.3, 2
Ex 3.3, 3
Ex 3.3, 4 Important
Ex 3.3, 5 (i) You are here
Ex 3.3, 5 (ii)
Ex 3.3, 6 (i)
Ex 3.3, 6 (ii) Important
Ex 3.3, 7 (i)
Ex 3.3, 7 (ii) Important
Ex 3.3, 8
Ex 3.3, 9
Ex 3.3, 10 (i) Important
Ex 3.3, 10 (ii)
Ex 3.3, 10 (iii) Important
Ex 3.3, 10 (iv)
Ex 3.3, 11 (MCQ) Important
Ex 3.3, 12 (MCQ)
Last updated at March 22, 2023 by Teachoo
Ex 3.3, 5 For the matrices A and B, verify that (AB) = B A where (i) A = [ 8([email protected] [email protected])] , B = [-1 2 1] Taking L.H.S (AB) Finding AB first AB =[ 8([email protected] [email protected])]_(3 1) "[ 1 2 1] " _(1 3) = [ 8(1 ( 1) &1 2&1 [email protected] 4 ( 1)& 4 2& 4 [email protected] ( 1)&3 2&3 1)]_(3 3) = [ 8( 1&2&[email protected]& 8& [email protected] 3&6&3)] AB = [ 8( 1&2&[email protected]& 8& [email protected] 3&6&3)] Now, (AB) = [ 8( 1&4& [email protected]& 8&[email protected]& 4&3)] Taking R.H.S B A Finding B , A Given B = [ 1 2 1] B = "[" "1 2 1]" ^ = [ 8( [email protected]@1)] Given A = [ 8([email protected] [email protected])] A = [1 4 1] Now, B A = [ 8( [email protected]@1)]_(3 1) "[1 4 3]" _(1 3) = [ 8( 1 1& 1 ( 4)& 1 [email protected] 1&2 ( 4)&2 [email protected] 1&1 ( 4)&1 3)]_(3 3) = [ 8( 1&4& [email protected]& 8&[email protected]& 4&3)] = L.H.S Hence L.H.S = R.H.S Hence proved