Home
Class 12
MATHS
If A (adj .A ) = 5I , where I is idensit...

If A (adj .A ) = 5I , where I is idensity martrix of order 3 , then |adj A | =

A

125

B

25

C

10

D

5

Text Solution

Verified by Experts

The correct Answer is:
B
Promotional Banner

Topper's Solved these Questions

  • MATHEMATICAL REASONING

    HIMALAYA PUBLICATION|Exercise Question Bank|97 Videos
  • MAXIMA AND MINIMA

    HIMALAYA PUBLICATION|Exercise QUESTION BANK|167 Videos

Similar Questions

Explore conceptually related problems

If A(adiA)=5I where I is the identity matrix of order 3 , then |adjA| is equal to

If A is a square matrix of order 3 and |A|=8 , then |adj A| =

If A is square matrix of order 3 and |A|=4 ,then find |adj A|

If A is square matrix of order 3 and |A| = 5 then find |Adj A| .

Let A=[(0,1),(0,0) ] show that (a I+b A)^n=a^n I+n a^(n-1)b A , where I is the identity matrix of order 2 and n in N .

A square matrix A, of order 3, has |A|=5, find |A.adj A|.

HIMALAYA PUBLICATION-MATRICES AND DETERMINANTS-QUESTION BANK
  1. If A and B are symmetric matrices of the same order, then which one of...

    Text Solution

    |

  2. If ((1,-tan theta ),(tan theta,1))((1,tan theta ),(-tan theta ,1))^(-1...

    Text Solution

    |

  3. If A (adj .A ) = 5I , where I is idensity martrix of order 3 , then |...

    Text Solution

    |

  4. If A=[[3,2],[4,5]] and A C=[[19,24],[37,46]], then C=

    Text Solution

    |

  5. If A= (a(ij) ) is a scalar matrix of order nxx n such that a(ii)=k for...

    Text Solution

    |

  6. Let A be an invertible matrix, which of the following is not true?

    Text Solution

    |

  7. If the matrix A B is a zero matrix, then

    Text Solution

    |

  8. The value of x for which the matrix product [[2,0,7],[0,1,0],[1,-2,...

    Text Solution

    |

  9. A square matrix can always be expressed as

    Text Solution

    |

  10. If A B=A and B A=B, then B^2=

    Text Solution

    |

  11. If A = [(i,0),(0,i)] then A^(4n) (n in N ) equals :

    Text Solution

    |

  12. If A = ((a,b),(c,d)) , such that ad - bc != 0 then A^(-1) is :

    Text Solution

    |

  13. If S=[[a,b],[c,d]] then adj A=

    Text Solution

    |

  14. If A= [[1, 0,0],[0,1, 0],[a, b,-1]] then A^2=

    Text Solution

    |

  15. If A= [[cos x, sin x],[-sin x, cos x]] and A(adj A)=k[[1,0],[0,1]] the...

    Text Solution

    |

  16. If A is 3 xx 4 matrix and B is a matrix such that A^(1)B and B A^(1) a...

    Text Solution

    |

  17. If A= [[1, x],[x^2,4 y]], B= [[-3,1],[1,0]] and adj A+B=[[1,0],[0,1]],...

    Text Solution

    |

  18. Let A= [[1,2],[-5,1]] and A^-1=x A+y I, then the values of x and y are

    Text Solution

    |

  19. If A=[[alpha,0],[1,1]] and B=[[1,0],[5,1]] then the value of alpha for...

    Text Solution

    |

  20. If A= [(alpha,2),(2,alpha)] and |A^(3)|= 125 " then " alpha =

    Text Solution

    |