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If A=[(1,0),(0,1)] then 7A^(3)+4A^(2)-11...

If `A=[(1,0),(0,1)]` then `7A^(3)+4A^(2)-11A=`………………..

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To solve the expression \( 7A^3 + 4A^2 - 11A \) where \( A = \begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix} \), we will follow these steps: ### Step 1: Calculate \( A^2 \) Since \( A \) is the identity matrix, we have: \[ A^2 = A \cdot A = \begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix} \cdot \begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix} = \begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix} \] ### Step 2: Calculate \( A^3 \) Next, we calculate \( A^3 \): \[ A^3 = A^2 \cdot A = \begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix} \cdot \begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix} = \begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix} \] ### Step 3: Substitute \( A \), \( A^2 \), and \( A^3 \) into the expression Now, substitute \( A \), \( A^2 \), and \( A^3 \) into the expression: \[ 7A^3 + 4A^2 - 11A = 7 \begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix} + 4 \begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix} - 11 \begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix} \] ### Step 4: Calculate the coefficients Calculating each term: \[ 7A^3 = \begin{pmatrix} 7 & 0 \\ 0 & 7 \end{pmatrix} \] \[ 4A^2 = \begin{pmatrix} 4 & 0 \\ 0 & 4 \end{pmatrix} \] \[ -11A = \begin{pmatrix} -11 & 0 \\ 0 & -11 \end{pmatrix} \] ### Step 5: Combine the matrices Now, combine these matrices: \[ 7A^3 + 4A^2 - 11A = \begin{pmatrix} 7 & 0 \\ 0 & 7 \end{pmatrix} + \begin{pmatrix} 4 & 0 \\ 0 & 4 \end{pmatrix} + \begin{pmatrix} -11 & 0 \\ 0 & -11 \end{pmatrix} \] \[ = \begin{pmatrix} 7 + 4 - 11 & 0 \\ 0 & 7 + 4 - 11 \end{pmatrix} = \begin{pmatrix} 0 & 0 \\ 0 & 0 \end{pmatrix} \] ### Final Answer Thus, the final result is: \[ \begin{pmatrix} 0 & 0 \\ 0 & 0 \end{pmatrix} \]
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ML KHANNA-MATRICES-PROBLEM SET(1) (FILL IN THE BLANKS)
  1. Is it possible to define the matrix A + B when a. A has 3 rows and B...

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  2. If 2X-Y=[(3,-3,0),(3,3,2)] and 2Y+X=[(4,1,5),(-1,4,-4)], then X=………………...

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  3. If [(4),(1),(3)]A=[(-4,8,4),(-1,2,1),(-3,6,3)] then A=……….

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  4. If A be any mxxn matrix and both AB and BA are defined then B should b...

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  5. If A=[(1,0),(0,1)] then 7A^(3)+4A^(2)-11A=………………..

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  6. If A=[(2,0,0),(0,2,0),(0,0,2)] then A^(2)=…………..

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  7. If A=[(1,2,2),(2,1,2),(2,2,1)] then A^(2)-4A-5I=………….

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  8. If A=[(1,0),(0,0)],B=[(0,1),(0 ,0)] then AB=………….

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  9. If A=[(2,3,1),(3,1,5)],B=[(1,2,-1),(0,-1,3)] then 2A-3B=………….

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  10. If A=[(9,1),(4,3)],B=[(1,5),(6,11)] and 3A+5B+2C=0 then C=………….

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  11. If A=[(2,-2,-4),(-1,3,4),(1,-2,x)] is an idempotent matrix, then x=………...

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  12. If A=[(2,1),(1,3)],B=[(3,2,0),(1,0,4)], then AB=…………..

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  13. If A=[(1,3,0),(-1,2,1),(0,0,2)],B=[(2,3,4),(1,2,3),(-1,1,2)] then AB=…...

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  14. If A=[(2,3,4),(1,2,3),(-1,1,2)],B=[(1,3,0),(-1,2,1),(0,0,2)], then AB+...

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  15. If A=[(0,1,1),(1,2,0),(4,-1,3)] then Adj. A=……….

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  16. The inverset of A=[(-4,-3,-3),(1,0,1),(4,4,3)] is ………

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  17. If A=[(cos theta, - sin theta, 0),(sin theta, cos theta, 0),(0,0,1)] t...

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  18. If A=[(1,2,3),(0,1,2),(0,0,1)] then A^(-1)=………..

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  19. The inverse of [(3,5,7),(2,-3,1),(1,1,2)] is ……………

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