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Consider the biorthogonal matrix propriety $\to$ $A^T \cdot B=I$.

How do I prove that $A \cdot B^T=I$?

Alessio K
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sam21551
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1 Answers1

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I assume that $A$ and $B$ are square matrices. Since $XY=I$ iff $YX=I$, we have $$ A^TB=I\Rightarrow BA^T=I\Rightarrow AB^T=(BA^T)^T=I. $$

user1551
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