Q11 of 74 Page 7

Let . Find (AB) – 1.

A =


|A| = 15 – 14 = 1


adj A =


A – 1 =


B =


|B| = 54 – 56 = – 2 adj B =


B – 1 =


Now, (AB) – 1 = B – 1A – 1


=


=


=


(AB) – 1 =


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