The task is to prove that for no two matrices A and B, A*B - B*A = I, where I is the identity matrix.(adsbygoogle = window.adsbygoogle || []).push({});

I tried multiplying by the inverses of A or B, but that doesn't seem to lead to a more manageable form. The only way I see this could be done is by writing down all n*n (assuming n by n matrices) linear equations. It's easy to do when n = 2, but the same contradiction may not be as obvious for higher n.

I hope there is a more intelligent way to go about this.

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# Homework Help: Disprove that AB-BA = I

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