Home
Class 12
MATHS
Suppose A is a matrix of order 3 and B=|...

Suppose A is a matrix of order 3 and `B=|A|A^(-1)`. If `|A|=5`, then `|B|` is equal to

A

`1`

B

`-5`

C

`-1`

D

`25`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the determinant of matrix \( B \), where \( B = |A| A^{-1} \) and \( |A| = 5 \). Here are the steps to find \( |B| \): ### Step-by-Step Solution: 1. **Understanding the Given Information**: We know that \( A \) is a matrix of order 3, and the determinant of \( A \) is given as \( |A| = 5 \). 2. **Expressing Matrix \( B \)**: The matrix \( B \) is defined as: \[ B = |A| A^{-1} \] Substituting the value of \( |A| \): \[ B = 5 A^{-1} \] 3. **Finding the Determinant of \( B \)**: We use the property of determinants that states: \[ |cA| = c^n |A| \] where \( c \) is a scalar and \( n \) is the order of the matrix \( A \). In our case, \( c = 5 \) and \( n = 3 \): \[ |B| = |5 A^{-1}| = 5^3 |A^{-1}| \] 4. **Finding the Determinant of \( A^{-1} \)**: The determinant of the inverse of a matrix is given by: \[ |A^{-1}| = \frac{1}{|A|} \] Therefore: \[ |A^{-1}| = \frac{1}{5} \] 5. **Substituting Back to Find \( |B| \)**: Now substituting \( |A^{-1}| \) back into the equation for \( |B| \): \[ |B| = 5^3 \cdot \frac{1}{5} = 125 \cdot \frac{1}{5} = 25 \] 6. **Final Result**: Thus, the determinant of matrix \( B \) is: \[ |B| = 25 \] ### Summary: The determinant \( |B| \) is equal to 25.

To solve the problem, we need to find the determinant of matrix \( B \), where \( B = |A| A^{-1} \) and \( |A| = 5 \). Here are the steps to find \( |B| \): ### Step-by-Step Solution: 1. **Understanding the Given Information**: We know that \( A \) is a matrix of order 3, and the determinant of \( A \) is given as \( |A| = 5 \). 2. **Expressing Matrix \( B \)**: ...
Promotional Banner

Topper's Solved these Questions

  • MATRICES

    MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS|Exercise MHT CET CORNER|18 Videos
  • MATRICES

    MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS|Exercise MHT CET CORNER|18 Videos
  • MATHEMATICAL LOGIC

    MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS|Exercise MHT CET CORNER|22 Videos
  • MHTCET 2007

    MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS|Exercise MATHEMATICS|50 Videos

Similar Questions

Explore conceptually related problems

If A is matrix of 3times3 order and |A|=625 ,then |(A)/(5)| is equal to

Let A and B are two non - singular matrices of order 3 such that A+B=2I and A^(-1)+B^(-1)=3I , then AB is equal to (where, I is the identity matrix of order 3)

If A be a square matrix of order 3, such that |A|=sqrt5 , then |Adj(-3A^(-2))| is equal to

Let A be a non - singular matrix of order 3 such that Aadj (3A)=5A A^(T) , then root3(|A^(-1)|) is equal to

If A is a square matrix of order 3,|A|=6,B=5A^(2) then find |B|

Let A be a matrix of order 3 such that A^(2)=3A-2I where, I is an identify matrix of order 3. If A^(5)=alphaa+betaI , then alphabeta is equal to

If A is a matrix of order 3xx3 , then |3A| is equal to………

If A is matrix of order 3 xx 2 and B is matrix of order 2 xx 3 , then what is |kAB|equal to (where k is any scalar quantity)?

MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS-MATRICES-MISCELLANEOUS PROBLEMS
  1. Let A =[(1,-1,1),(2,1,-3),(1,1,1)] and 10B=[(4,2,2),(-5,0,alpha),(...

    Text Solution

    |

  2. If A(theta)=[(1, than theta),(-tan, theta=1)] and AB=l, then (sec^(2)t...

    Text Solution

    |

  3. If A=[(cos alpha, -sin alpha, 0),(sin alpha, cos alpha,0),(0,0,1)] the...

    Text Solution

    |

  4. Suppose A is a matrix of order 3 and B=|A|A^(-1). If |A|=5, then |B| i...

    Text Solution

    |

  5. if[{:(2,1),(3,2):}]A[{:(-3,2),(5,-3):}]=[{:(1,0),(0,1):}],"then" A=?

    Text Solution

    |

  6. If f(theta)=[(cos theta, -sin theta,0),(sin theta, cos theta, 0),(0,0,...

    Text Solution

    |

  7. If A is a singular matrix, then Aadj(A) is a/an

    Text Solution

    |

  8. If k is a scalar and l is a unit matrix of order 3 then adj(kl) is equ...

    Text Solution

    |

  9. Consider the system of equations x+y+z=6 x+2y+3z=10 x+2y+lambda...

    Text Solution

    |

  10. Let a, b, c be any real numbers. Suppose that there are real numbers...

    Text Solution

    |

  11. Let a, b, c be positive real numbers. The following system of equation...

    Text Solution

    |

  12. If the system of linear equations x+2ay +az =0,x+3by+bz =0 and x+4cy ...

    Text Solution

    |

  13. The symmetric part of the matrix A=[(1,2,4),(6,8,2),(2,-2,7)] is equal...

    Text Solution

    |

  14. If {:A=[(1,0,0),(0,1,0),(a,b,-1)]:}, then A^2 is equal to

    Text Solution

    |

  15. If A=[1 2 2 2 1-2a2b] is a matrix satisfying the equation AA^T=""9I , ...

    Text Solution

    |

  16. If A is a 3xx3 such that |5.adj(A)|=5 then |A| is equal to

    Text Solution

    |

  17. If A=[(alpha, 2),(2, alpha)] and |A^(3)|=27 then alpha is equal to

    Text Solution

    |

  18. The elements in the first row and third column of the inverse of the m...

    Text Solution

    |

  19. If A=[(-1,3),(2,1)] then 1+A+A^(2)+…………..+oo is equal to

    Text Solution

    |

  20. if A=[[1,-2] , [4,5]] and f(t)=t^2-3t+7 then f(A)+[[3,6],[-12,-9]]=

    Text Solution

    |