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If A is a square matrix of order n and A...

If A is a square matrix of order n and `A A^T = I` then find `|A|`

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Given,`A A^T=I`
=`A^(−1)=A^T `
=`A^T=adj(A) `
(∣A∣=1)
Every element of A is equal to it's co-factor.
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