How do you prove that the product of two orthogonal matrices is orthogonal? I know that a matrix can be written in component form as [tex]A=a_{jk}[/tex] and that for an orthogonal matrix, the inverse equals the transpose so [tex]a_{kj}=(a^{-1})_{jk}[/tex] and matrix multiplication can be expressed as [tex]AB=\Sigma_ka_{jk}b_{kl}[/tex]. I think that is all I need to be using, but I'm not sure where to go from there.(adsbygoogle = window.adsbygoogle || []).push({});

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# Matrix Proof

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