The question is: Suppose one has n×n square matrices X, Y and Z such that(adsbygoogle = window.adsbygoogle || []).push({});

XY = I and Y Z = I. Show that it follows that X = Z.

Now if this were XY and ZY, I would just say that:

XY=ZY -> XY-ZY=0 ->Y(X-Z)=0 -> X-Z=0 -> X=Z.

I am wondering that since the Y is on different sides of the Z and X this still holds? Thanks!

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# Easy Linear Algebra Question

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