Find the adjoint of each of the following Matrices.


Verify that (adj A) A=|A| I=A (adj A) for the above matrices.

A =


Cofactors of A are


C11 = 4


C12 = – 2


C21 = – 5


C22 = – 3


Since, adj A =


(adj A) =


=


Now, (adj A)A =


(adj A)A =


And, |A|.I =


Also, A(adj A) =


A(adj A) =


Hence, (adj A)A = |A|.I = A.(adj A)


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