Construct a 3×4 matrix A = [ajj] whose elements ajj are given by :

ajj = i – j

Let A = [aij]2×3

So, the elements in a 3×4 matrix are


a11, a12, a13, a14, a21, a22, a23,a24,a31,a32,a33,a34


A = …… (1)


a11 = 1 – 1 = 0 a12 = 1 – 2 = – 1 a13 = 1 – 3 = – 2 a14 = 1 – 4 = – 3


a21 = 2 – 1 = 1 a22 = 2 – 2 = 0 a23 = 2 – 3 = – 1 a24 = 2 – 4 = – 2


a31 = 3 – 1 = 2 a32 = 3 – 2 = 1 a33 = 3 – 3 = 0 a34 = 3 – 4 = – 1


So, from (1)


A =


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