Find adjoint of each of the matrices. \(\begin{bmatrix}1&2\\3&4\end{bmatrix}\)
Find adjoint of each of the matrices. \(\begin{bmatrix}1&2\\3&4\end{bmatrix}\)
Solution and Explanation
Let A=\(\begin{bmatrix}1&2\\3&4\end{bmatrix}\)
we have A11=4, A12=-3, A21=-2, A22=1
so adj A=\(\begin{bmatrix}A_{11}&A_{12}\\A_{21}&A_{22}\end{bmatrix}\)
=\(\begin{bmatrix}4&-2\\-3&1\end{bmatrix}\)
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