A =

|A| = 15 – 14 = 1

adj A =

A ^{– 1} =

B =

|B| = 54 – 56 = – 2 adj B =

B ^{– 1} =

Now, (AB) ^{– 1 =} B ^{– 1}A ^{– 1}

=

=

=

(AB) ^{– 1 =}