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Let $A$ be a $2 \times 3$ matrix with real entries and let $B$ be a $3 \times 2$ matrix with real entries.
If $\det(AB)=4$ then find the value of $\det(BA)$.
I am aware that $\det(AB)=\det(BA)$ when $A$ and $B$ are of same order. But how to do this?