Question

answer this plzz. I need help​

Answer 1

• GiveN :

$\mapsto \: \: \sf \: A=\left[\begin {array}{cc} \sf1& \sf1\\ \sf \: 5& \sf \: 1\end{array}\right]$

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• To FienD :

$\mapsto \sf \: \: Adj \: \: A= Adj \: \left[\begin {array}{cc} \sf1& \sf1\\ \sf \: 5& \sf \: 1\end{array}\right] = {?}$

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• SolutioN :

$\mapsto \sf \: \: Adj \: \: A= Adj \: \left[\begin {array}{cc} \sf1& \sf1\\ \sf \: 5& \sf \: 1\end{array}\right]$

$\implies \: \sf \: Adj \: \left[\begin {array}{cc} \: \sf 1& \sf \: - 1\\ \sf \: - 5& \: \: \: \: \sf \: 1\end{array}\right]$

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• ConcepT BoosteR :

$\mapsto \sf Adjugate \: \: or \: \: Adjoint \: \: of \: \: a \: \: Matrix = \: transpose \: \: of \: \: its \: \: cofactor$

$\mapsto \sf \: Relation \: \: between \: \: det \: A \: \: and \: \: Adj \: A : A^{-1} = \frac{Adj \: A}{det \: A}$

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HOPE THIS IS HELPFUL...