Find the adjoint of each of the following Matrices. Verify that (adj A) A=|A| I=A (adj A) for the above matrices.

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 = 1

C₁₂ =

C₂₁ =

C₂₂ = 1

Since, adj A =

(adj A) =

=

Now, (adj A)A =

=

(adj A)A =

And, |A|.I =

=

Also, A(adj A) =

=

=

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

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