Question
Find (a) $\operatorname{det}(A),$ (b) the matrix of cofactors $M_{C},(\mathrm{c})$ adj $(A),$ and, if possible, $(\mathrm{d}) A^{-1}.$$$A=\left[\begin{array}{rr}-1 & -2 \\4 & 1\end{array}\right]$$
Step 1
So, for the given matrix A, we have $det(A) = (-1*1) - (4*-2) = -1 + 8 = 7$. Show more…
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