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(A) We know that for any invertible matrix $A$,$\operatorname{Adj}(A) = |A| A^{-1}$.Given that $P$ and $Q$ are invertible matrices,their product $QP$

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$\operatorname{Adj}(P) \operatorname{Adj}(Q)$

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(A) We know that for any invertible matrix $A$,$\operatorname{Adj}(A) = |A| A^{-1}$.Given that $P$ and $Q$ are invertible matrices,their product $QP$ is also an invertible matrix.Therefore,$\operatorname{Adj}(QP) = |QP| (QP)^{-1}$.Using the properties of determinants,$|QP| = |Q||P| = |P||Q|$.Using the property of inverse matrices,$(QP)^{-1} = P^{-1} Q^{-1}$.Thus,$\operatorname{Adj}(QP) = |P||Q| P^{-1} Q^{-1}$.However,note that $\operatorname{Adj}(Q) = |Q| Q^{-1}$ and $\operatorname{Adj}(P) = |P| P^{-1}$.Multiplying these,we get $\operatorname{Adj}(Q) \operatorname{Adj}(P) = (|Q| Q^{-1}) (|P| P^{-1}) = |Q||P| Q^{-1} P^{-1}$.Since $\operatorname{Adj}(QP) = |QP| (QP)^{-1} = |Q||P| P^{-1} Q^{-1}$,and generally $P^{-1} Q^{-1} 
eq Q^{-1} P^{-1}$,the standard identity is $\operatorname{Adj}(QP) = \operatorname{Adj}(P) \operatorname{Adj}(Q)$.

If $P$ and $Q$ are two invertible matrices of the same order,then $\operatorname{Adj}(QP)$ is equal to

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