Let A = [ aii] be required 3 x 4 matrix where aij= i.j
a11 = 1 . 1 = 1, a12 =1 . 2 = 2, a13 = 1 . 3 = 3, a14 = 1 . 4 = 4
a21 = 2 . 1 = 2, a22 =2 . 2 = 4, a23 = 2 . 3 = 6, a24 = 2 . 4 = 8
a31 = 3 . 1 = 3, a32 =3 . 2 = 6, a33 = 3 . 3 = 9, a34 = 3 . 4 = 12