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[{:(1,-1),(2,3):}] find the inverse of m...

`[{:(1,-1),(2,3):}]` find the inverse of matrix

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To find the inverse of the matrix \[ A = \begin{pmatrix} 1 & -1 \\ 2 & 3 \end{pmatrix} \], we will follow these steps: ### Step 1: Calculate the Determinant of A The determinant of a 2x2 matrix \[ \begin{pmatrix} a & b \\ c & d \end{pmatrix} \] is given by the formula: \[ \text{det}(A) = ad - bc \] For our matrix: - \( a = 1 \) - \( b = -1 \) - \( c = 2 \) - \( d = 3 \) Calculating the determinant: \[ \text{det}(A) = (1)(3) - (-1)(2) = 3 + 2 = 5 \] ### Step 2: Find the Adjoint of A The adjoint of a 2x2 matrix is obtained by swapping the elements on the main diagonal and changing the signs of the off-diagonal elements. For the matrix \( A \): - Swap \( a \) and \( d \): \( 1 \) and \( 3 \) - Change the signs of \( b \) and \( c \): \( -1 \) and \( 2 \) Thus, the adjoint of \( A \) is: \[ \text{adj}(A) = \begin{pmatrix} 3 & 1 \\ -2 & 1 \end{pmatrix} \] ### Step 3: Calculate the Inverse of A The inverse of a matrix \( A \) is given by the formula: \[ A^{-1} = \frac{1}{\text{det}(A)} \cdot \text{adj}(A) \] Substituting the values we found: \[ A^{-1} = \frac{1}{5} \cdot \begin{pmatrix} 3 & 1 \\ -2 & 1 \end{pmatrix} \] Calculating the inverse: \[ A^{-1} = \begin{pmatrix} \frac{3}{5} & \frac{1}{5} \\ -\frac{2}{5} & \frac{1}{5} \end{pmatrix} \] ### Final Answer The inverse of the matrix \( A \) is: \[ A^{-1} = \begin{pmatrix} \frac{3}{5} & \frac{1}{5} \\ -\frac{2}{5} & \frac{1}{5} \end{pmatrix} \] ---

To find the inverse of the matrix \[ A = \begin{pmatrix} 1 & -1 \\ 2 & 3 \end{pmatrix} \], we will follow these steps: ### Step 1: Calculate the Determinant of A The determinant of a 2x2 matrix \[ \begin{pmatrix} a & b \\ c & d \end{pmatrix} \] is given by the formula: \[ \text{det}(A) = ad - bc \] For our matrix: ...
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