If A is the 2 !! 2 matrix given by A = [[a, b], [c, d]] and if ad - bc ? 0, the inverse is given by A^-1 = 1/(ad - bc) [[d, -b], [-c, a]]. Use the formula above to find the inverse of the 2 !! 2 matrix (if it exists). (If an answer does not exist, enter DNE.) [[1, -4], [-5, 4]] Find the inverse of the elementary matrix. [[1, 0, 0], [0, 1, 0], [0, -3, 1]]
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First, let's write down the given matrix A: A = $\begin{bmatrix} -5 & a \\ -1 & b \end{bmatrix}$ Now, let's find the determinant of A, which is given by: $det(A) = (-5)(b) - (-1)(a) = -5b + a$ Show more…
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