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Let A be a square matrix of order 3xx3, ...

Let A be a square matrix of order `3xx3`, then `|k A|`is equal to(A) `k|A|` (B) `k^2|A|` (C) `k^3|A|` (D) `3k |A|`

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To solve the problem, we need to find the determinant of the matrix \( kA \), where \( A \) is a \( 3 \times 3 \) matrix and \( k \) is a scalar. ### Step-by-Step Solution: 1. **Define the Matrix \( A \)**: Let \( A \) be a \( 3 \times 3 \) matrix represented as: \[ A = \begin{pmatrix} a_{11} & a_{12} & a_{13} \\ a_{21} & a_{22} & a_{23} \\ a_{31} & a_{32} & a_{33} \end{pmatrix} \] 2. **Multiply the Matrix by Scalar \( k \)**: The matrix \( kA \) is obtained by multiplying each element of \( A \) by the scalar \( k \): \[ kA = \begin{pmatrix} k \cdot a_{11} & k \cdot a_{12} & k \cdot a_{13} \\ k \cdot a_{21} & k \cdot a_{22} & k \cdot a_{23} \\ k \cdot a_{31} & k \cdot a_{32} & k \cdot a_{33} \end{pmatrix} \] 3. **Apply the Determinant Property**: The property of determinants states that if a matrix is multiplied by a scalar \( k \), the determinant of the resulting matrix is equal to \( k^n \) times the determinant of the original matrix, where \( n \) is the order of the matrix. For a \( 3 \times 3 \) matrix, \( n = 3 \): \[ |kA| = k^3 |A| \] 4. **Conclusion**: Therefore, the determinant of the matrix \( kA \) is given by: \[ |kA| = k^3 |A| \] 5. **Identify the Correct Option**: From the options provided, the correct answer is: \[ (C) \, k^3 |A| \]

To solve the problem, we need to find the determinant of the matrix \( kA \), where \( A \) is a \( 3 \times 3 \) matrix and \( k \) is a scalar. ### Step-by-Step Solution: 1. **Define the Matrix \( A \)**: Let \( A \) be a \( 3 \times 3 \) matrix represented as: \[ A = \begin{pmatrix} ...
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NAGEEN PRAKASHAN ENGLISH-DETERMINANTS-Exercise 4.2
  1. Using the property of determinants and without expanding in questions ...

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  2. Using the property of determinants and without expanding in questions ...

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  3. Using the property of determinants and without expanding, prove that |...

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  4. Using the property of determinants and without expanding, prove that:...

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  5. Using the property of determinants and without expanding, prove that:...

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  6. Using the property of determinants and without expanding, prove that:...

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  7. Using the property of determinants and without expanding, prove that:...

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  8. By using properties of determinants. Show that:(i) |1a a^2 1bb^2 1cc^2...

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  9. Using the properties of determinants, show that: [[x, x^2, yz],[y, y...

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  10. By using properties of determinants. Show that: (i) |x+4 2x2x2xx+4 2x2...

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  11. By using properties of determinants. Show that:(i) |a-b-c2a2a2bb-c-a2b...

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  12. Using properties of determinants, prove the following: |1xx^2x^2 1...

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  13. By using properties of determinants. Show that:|1+a^2-b^2 2a b-2b2a b1...

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  14. Using properties of determinants, prove the following: |[a^2 + 1,ab, ...

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  15. Let A be a square matrix of order 3xx3, then |k A|is equal to(A) k|A|...

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  16. Which of the following is correct (A) Determinant is a square matrix. ...

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