If A = [aij] is a square matrix of order 2 such that aij = {(1,  when i ≠j 0,  when i=j  )┤ , then A2 is :

(a) [8(1 0 1 0)]  (b) [8(1 1 0 0)]      (c) [8(1 1 1 0)]  (d) [8(1 0 0 1)] 

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Question 3 If A = [𝑎𝑖𝑗] is a square matrix of order 2 such that 𝑎𝑖𝑗 = {█(1, 𝑤ℎ𝑒𝑛 𝑖 ≠𝑗@0, 𝑤ℎ𝑒𝑛 𝑖=𝑗 )┤ , then A2 is : (a) [■8(1&0@1&0)] (b) [■8(1&1@0&0)] (c) [■8(1&1@1&0)] (d) [■8(1&0@0&1)] For a 2 × 2 matrix A = [■8(𝑎_11&𝑎_12@𝑎_21&𝑎_22 )] Given that 𝑎_𝑖𝑗={█(1, 𝑖≠ 𝑗@0, 𝑖=𝑗)┤ Thus, 𝑎_11 = 0, 𝑎_22 = 0 , 𝑎_12 = 1, 𝑎_21 = 1 So, our matrix becomes A = [■8(𝟎&𝟏@𝟏&𝟎)] Now, A2 = [■8(0&1@1&0)][■8(0&1@1&0)] = [■8(0(0)+1(1)&0(1)+1(0)@1(0)+0(1)&1(1)+0(0))] = [■8(𝟏&𝟎@𝟎&𝟏)] So, the correct answer is (d)

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Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 13 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.