Find the inverse of each of the following matrices.

|A| =


= 1(6 – 1) – 2(4 – 3) + 3(2 – 9)


= 5 – 2 – 21


= – 18


Hence, A – 1 exists


Cofactors of A are:


C11 = 5 C21 = – 1 C31 = – 7


C12 = – 1 C22 = – 7 C32 = 5


C13 = – 7 C23 = 5 C33 = – 1


adj A =


=


So, adj A =


Now, A – 1 = .adj A


So, A – 1 = .


Hence, A – 1 =


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