Home
Class 12
MATHS
If A is an orthogonal matrix of order 3 ...

If A is an orthogonal matrix of order 3 and B = `[{:(1,2,3),(-3,0,2),(2,5,0):}]`, then which of the following is/are correct ?
1. `|AB|= +- 47`
2. AB = BA
Select the correct answer using the code given below :

A

1 only

B

2 only

C

Both 1 and 2

D

Neither 1 nor 2

Text Solution

Verified by Experts

The correct Answer is:
A

The determinent of a orthogonal matrix is always `pm1`
`|A|= pm1`
`B=[(1,2,3),(-3,0,2),(2,5,0)]`
`|B|=-10-2(-4)+3(-15)`
`=-47`
`|AB|=|A||B|`
`=(pm1)(-47)`
Promotional Banner

Topper's Solved these Questions

  • INDEFINITE INTEGRATION

    NDA PREVIOUS YEARS|Exercise MCQ|59 Videos
  • PAIR OF STRAIGHT LINES

    NDA PREVIOUS YEARS|Exercise Example|12 Videos

Similar Questions

Explore conceptually related problems

If A is an orthogonal matrix of order 3 and B=[[1,2,3-3,0,22,5,0]] then which of the following is/are correct?

A=[{:(3,1),(0,4):}]and B = [{:(1,1),(0,2):}] , then which of the following is/are correct ? I. AB is defined II. BA is defined III. AB = BA Select the correct answer using the codes given below.

If A=[{:(3,1),(0,4):}] and B = [{:(1,1),(0,2):}] , then which of the following is/are correct ? I. AB is defined II. BA is defined III. AB=BA Select the correct answer using the code given below :

If a+b+c=0 , then which of the following is/are correct? 1. a,b,c are coplanar 2. a xx b=b xx c=c xx a Select the correct answer using the codes given below

A=[{:(1,-1),(2,3):}]and B=[{:(2,3),(-1,-2):}] , then which of the following is/are correct ? 1. AB(A^(-1)B^(-1)) is a unit matrix. 2. (AB)^(-1)=A^(-1)B^(-1) Select the correct answer using the code given below :

IF A=pi//6 and B=pi//3 then which of the following is/are correct? 1. sinA+sinB=cos A+cos B 2. tanA+ tan B=cot A+ cot B Select the correct answer using the code given below:

If A=[{:(1,1,-1),(2,-3,4),(3,-2,3):}]and B=[{:(-1,-2,-1),(6,12,6),(5,10,5):}] then which of the following is/are correct ? 1. A and B commute. 2. AB is a null matrix. Select the correct answer using the code given below :

If A=|x inIR:x^(2)+6x-7lt0} and B={x inIR:x^(2)+9x+14gt0} , then which of the following is/are correct? 1. (AnnB)=(-2,1) 2. (A//B)=(-7,-2) Select the correct answer using the code given below:

If A=[{:(1,-1),(2,3):}] and B=[{:(2,3),(-1,-2):}] then which of the following is/are correct ? 1. AB (A^(-1)B^(-1)) is a unit matrix. 2. (AB)^(-1)=A^(-1)B^(-1) Select the correct answer using the codes given below :

Let f(x)=[|x|-|x-1|]^(2) Which of the following equation is/are correct? 1. f(-2)=f(5) 2. f''(-2)+f''(0.5)+f''(3)=4 Select the correct answer using the code given below:

NDA PREVIOUS YEARS-MATRICES & DETERMINANTS-MQS
  1. If A=[{:(1,1,-1),(2,-3,4),(3,-2,3):}]and B=[{:(-1,-2,-1),(6,12,6),(5,1...

    Text Solution

    |

  2. If A is an invertible matrix of order n and k is any positive real num...

    Text Solution

    |

  3. If A is an orthogonal matrix of order 3 and B = [{:(1,2,3),(-3,0,2),(2...

    Text Solution

    |

  4. If a, b, c are real numbers, then the value the determinant |(1-a,a-...

    Text Solution

    |

  5. Cosider the function f(x)=|{:(x^(3),sin x,cos x),(6,-1,0),(p,p^(2),p^(...

    Text Solution

    |

  6. Cosider the function f(x)=|{:(x^(3),sin x,cos x),(6,-1,0),(p,p^(2),p^(...

    Text Solution

    |

  7. If A is a square matrix, then what is adj A^(T) - (adj A)^(T) equal to...

    Text Solution

    |

  8. Consider the following in respect of the matrix A=({:(-1,1),(1,-1):}):...

    Text Solution

    |

  9. Which of the following determinants have value 'zero'? 1. |{:(41,1,...

    Text Solution

    |

  10. The system of linear equations kx + y + z = 1, x + ky + z = 1 and x + ...

    Text Solution

    |

  11. If A is semy square matrix of order 3 and det A = 5, then what is det[...

    Text Solution

    |

  12. What is [x" "y" "z][{:(a,h,g),(h,b,f),(g,f,c):}]equal to ?

    Text Solution

    |

  13. Let ax^3+bx^2+cx+d =|(x+1,2x,3x),(2x+3,x+1,x), (2-x,3x+4,5x-1)| then w...

    Text Solution

    |

  14. Let ax^3+bx^2+cx+d =|(x+1,2x,3x),(2x+3,x+1,x), (2-x,3x+4,5x-1)| then w...

    Text Solution

    |

  15. If m=[[1,0],[0,1]]and n=[[0,1],[-1,0]], then what is the value of the ...

    Text Solution

    |

  16. If f{x}=[{:(cos x,-sinx,0),(sin x,cos x,0),(" "0," "0,1):}], then whic...

    Text Solution

    |

  17. Which of the following are correct in respect of the system of equatio...

    Text Solution

    |

  18. A=[{:(1,-1),(2,3):}]and B=[{:(2,3),(-1,-2):}], then which of the follo...

    Text Solution

    |

  19. For the system of linear equations 2x+3y+5z=9, 7x+3y-2z=8 and 2x+3y+l...

    Text Solution

    |

  20. For the system of linear equations 2x+3y+5z=9, 7x+3y-2z=8 and 2x+3y+l...

    Text Solution

    |