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Question
If A is an invertible matrix, then det (A−1) is equal to ____________ .
Options
det (A)
\[\frac{1}{det \left( A \right)}\]
1
none of these
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Solution
\[\frac{1}{det \left( A \right)}\]
We know that for any invertible matrix A,
\[\left| A^{- 1} \right|\]
\[\frac{1}{\left| A \right|}\]
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