Problem

Find the inverse of the matrix \[ A = \begin{pmatrix} 2 & 3 \ 4 & 5 \end{pmatrix} \]

Answer

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Answer

Finally, multiplying the scalar \(\frac{1}{-2}\) with the matrix, we get the inverse matrix \[ A^{-1} = \begin{pmatrix} -5/2 & 3/2 \ 2 & -1 \end{pmatrix} \]

Steps

Step 1 :The given matrix is \[ A = \begin{pmatrix} 2 & 3 \ 4 & 5 \end{pmatrix} \]

Step 2 :The formula to find the inverse of a 2x2 matrix \[ A = \begin{pmatrix} a & b \ c & d \end{pmatrix} \] is \[ A^{-1} = \frac{1}{ad-bc} \begin{pmatrix} d & -b \ -c & a \end{pmatrix} \]

Step 3 :We substitute the values a=2, b=3, c=4, d=5 into the formula to get \[ A^{-1} = \frac{1}{2*5 - 3*4} \begin{pmatrix} 5 & -3 \ -4 & 2 \end{pmatrix} \]

Step 4 :Solving for the determinant, ad-bc, we get -2. Substituting this into the formula, we get \[ A^{-1} = \frac{1}{-2} \begin{pmatrix} 5 & -3 \ -4 & 2 \end{pmatrix} \]

Step 5 :Finally, multiplying the scalar \(\frac{1}{-2}\) with the matrix, we get the inverse matrix \[ A^{-1} = \begin{pmatrix} -5/2 & 3/2 \ 2 & -1 \end{pmatrix} \]

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