Let A be any 3 $ \times $ 3 invertible matrix. Then which one of the following is not always true ?

Question

Let A be any 3 $ \times $ 3 invertible matrix. Then which one of the following is not always true ?

adj (A) = $\left| \right.$A$\left| \right.$.A^$-$1

adj (adj(A)) = $\left| \right.$A$\left| \right.$.A

adj (adj(A)) = $\left| \right.$A$\left| \right.$².(adj(A))^$-$1

adj (adj(A)) = $\left| \, \right.$A $\left| \, \right.$.(adj(A))^$-$1

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