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Consider the matrix A=[{:(2,3),(4,5):}]....

Consider the matrix `A=[{:(2,3),(4,5):}]`.
Hence , find `A^(-1)`.

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To find the inverse of the matrix \( A = \begin{pmatrix} 2 & 3 \\ 4 & 5 \end{pmatrix} \), we can follow these steps: ### Step 1: Calculate the Determinant of A The determinant of a 2x2 matrix \( A = \begin{pmatrix} a & b \\ c & d \end{pmatrix} \) is calculated using the formula: \[ \text{det}(A) = ad - bc \] For our matrix \( A \): - \( a = 2 \) - \( b = 3 \) - \( c = 4 \) - \( d = 5 \) Thus, the determinant is: \[ \text{det}(A) = (2)(5) - (3)(4) = 10 - 12 = -2 \] ### Step 2: Find the Adjoint of A The adjoint of a 2x2 matrix \( A = \begin{pmatrix} a & b \\ c & d \end{pmatrix} \) is given by: \[ \text{adj}(A) = \begin{pmatrix} d & -b \\ -c & a \end{pmatrix} \] For our matrix \( A \): - \( d = 5 \) - \( -b = -3 \) - \( -c = -4 \) - \( a = 2 \) Thus, the adjoint is: \[ \text{adj}(A) = \begin{pmatrix} 5 & -3 \\ -4 & 2 \end{pmatrix} \] ### Step 3: Calculate the Inverse of A The inverse of matrix \( A \) is given by the formula: \[ A^{-1} = \frac{1}{\text{det}(A)} \cdot \text{adj}(A) \] Substituting the values we found: \[ A^{-1} = \frac{1}{-2} \cdot \begin{pmatrix} 5 & -3 \\ -4 & 2 \end{pmatrix} \] This simplifies to: \[ A^{-1} = \begin{pmatrix} \frac{5}{-2} & \frac{-3}{-2} \\ \frac{-4}{-2} & \frac{2}{-2} \end{pmatrix} = \begin{pmatrix} -\frac{5}{2} & \frac{3}{2} \\ 2 & -1 \end{pmatrix} \] ### Final Answer Thus, the inverse of the matrix \( A \) is: \[ A^{-1} = \begin{pmatrix} -\frac{5}{2} & \frac{3}{2} \\ 2 & -1 \end{pmatrix} \] ---
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MODERN PUBLICATION-DETERMINANTS-Exercise 4(g) (SHORT ANSWER TYPE QUESTIONS)
  1. Verify A(adj.A)=(adj.A)A=|A|I: [{:(2,3),(-4,-6):}]

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  2. Verify A(adj.A)=(adj.A)A=|A|I: [{:(1,-1,2),(3,0,-2),(1,0,3):}]

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  3. Verify that A(adjA)=I when : A=[{:(cos theta, -sintheta,0),(sintheta,...

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  4. Find the inverse of each of the following matrice : [{:(-1,5),(-3,2)...

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  5. Find the inverse of each of the following matrice : [{:(2,-2),(4,3):...

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  6. If A=[{:(2,-1),(-1,2):}], verify A^(2)-4A+3I=0, where I=[{:(1,0),(0,1)...

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  7. If A=[{:(3,1),(-1,2):}], show that A^(2)-5A+7I=O. Hence, find A^(-1).

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  8. Consider the matrix A=[{:(2,3),(4,5):}]. Show that A^(2)-7A-2I=O

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  9. Consider the matrix A=[{:(2,3),(4,5):}]. Hence , find A^(-1).

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  10. If A=[{:(2,3),(5,-2):}], write A^(-1) in terms of A.

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  11. Verify (AB)^(-1)=B^(-1)A^(-1) for the matrices A and B where A=[{:(2...

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  12. Verify (AB)^(-1)=B^(-1)A^(-1) for the matrices A and B where A=[{:(3...

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  13. Verify (AB)^(-1)=B^(-1)A^(-1) for the matrices A and B where A=[{:(3...

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  14. Verify (AB)^(-1)=B^(-1)A^(-1) for the matrices A and B where A=[{:(4...

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  15. Show that the matrix A=[{:(2,3),(1,2):}] satisfies the equation A^(2)-...

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  16. If A=[{:(2,-1),(1,3):}] , then show that A^(2)-5A+7I(2)=O, hence find ...

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  17. If A=[3 1-1 2] , show that A^2-5A+7I=O . Hence, find A^(-1) .

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  18. For the matrix A=[{:(2,1),(3,0):}] , find the numbers 'a' and 'b' such...

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  19. If A=[{:(2,-3),(-4,7):}], compute A^(-1) and show that 2A^(-1)+A-9I=O.

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