If a = [ 3 1 2 − 3 ] , Then Find |Adj A|. - Mathematics

Question

If \[A = \begin{bmatrix}3 & 1 \\ 2 & - 3\end{bmatrix}\], then find |adj A|.

Solution

\[\left| A \right| = \begin{vmatrix}3 & 1 \\ 2 & - 3\end{vmatrix} = - 11\]
\[ \therefore \left| adj A \right| = \left| A \right|^{n - 1} = \left( - 11 \right)^{2 - 1} = - 11\]

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Properties of Matrix Multiplication - Inverse of a Square Matrix by the Adjoint Method

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Q 26 Q 25 Q 27

Chapter 7: Adjoint and Inverse of a Matrix - Exercise 7.3 [Page 36]

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RD Sharma Mathematics [English] Class 12

Chapter 7 Adjoint and Inverse of a Matrix
Exercise 7.3 | Q 26 | Page 36

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