If , show that adj A=A.

A =


Cofactors of A


C11 = – 4 C21 = – 3 C31 = – 3


C12 = 1 C22 = 0 C32 = 1


C13 = 4 C23 = 4 C33 = 3


adj A =


=


So, adj A =


Hence, adj A = A


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