Home
Class 12
MATHS
If u, v and w (all positive) are the p^(...

If u, v and w (all positive) are the `p^(th), q^(th) and r^(th)` terms of a GP, the determinant of the matrix `({:("In",u,pl),("In",v,ql),("In",w,rl):})`is

A

0

B

1

C

(p - q) (q - r) (r - p)

D

In u `xx` In v `xx` In w

Text Solution

AI Generated Solution

The correct Answer is:
To find the determinant of the matrix formed by the logarithms of the terms of a geometric progression (GP), we can follow these steps: ### Step-by-Step Solution: 1. **Identify the terms of the GP**: Let the first term of the GP be \( a \) and the common ratio be \( r \). Then the \( p^{th}, q^{th}, \) and \( r^{th} \) terms can be expressed as: \[ u = ar^{p-1}, \quad v = ar^{q-1}, \quad w = ar^{r-1} \] 2. **Take logarithms of the terms**: We take the natural logarithm of each term: \[ \log u = \log(ar^{p-1}) = \log a + (p-1) \log r \] \[ \log v = \log(ar^{q-1}) = \log a + (q-1) \log r \] \[ \log w = \log(ar^{r-1}) = \log a + (r-1) \log r \] 3. **Set up the matrix**: We can now form the matrix with these logarithmic values: \[ \begin{pmatrix} \log u & p & 1 \\ \log v & q & 1 \\ \log w & r & 1 \end{pmatrix} \] 4. **Substituting the logarithmic values**: Substitute the logarithmic expressions into the matrix: \[ \begin{pmatrix} \log a + (p-1) \log r & p & 1 \\ \log a + (q-1) \log r & q & 1 \\ \log a + (r-1) \log r & r & 1 \end{pmatrix} \] 5. **Perform row operations**: To simplify the determinant, we can perform row operations. We can subtract the first row from the second and third rows: \[ R_2 \leftarrow R_2 - R_1 \] \[ R_3 \leftarrow R_3 - R_1 \] This gives us: \[ \begin{pmatrix} \log a + (p-1) \log r & p & 1 \\ (q - p) + ((q-1) - (p-1)) \log r & 0 & 0 \\ (r - p) + ((r-1) - (p-1)) \log r & 0 & 0 \end{pmatrix} \] 6. **Calculate the determinant**: The determinant of a matrix with two rows of zeros is zero. Therefore, the determinant of the matrix is: \[ \text{Det} = 0 \] ### Final Result: The determinant of the matrix is: \[ \boxed{0} \]

To find the determinant of the matrix formed by the logarithms of the terms of a geometric progression (GP), we can follow these steps: ### Step-by-Step Solution: 1. **Identify the terms of the GP**: Let the first term of the GP be \( a \) and the common ratio be \( r \). Then the \( p^{th}, q^{th}, \) and \( r^{th} \) terms can be expressed as: \[ u = ar^{p-1}, \quad v = ar^{q-1}, \quad w = ar^{r-1} ...
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 b c are the p^(th),q^(th) and r^(th) terms of an AP then prove that sum a(q-r)=0

If p^(th),q^(th) and r^(th) terms of an A.P.are in G.P. then the common ratio of G.P.is-

l, m,n are the p^(th), q ^(th) and r ^(th) term of a G.P. all positive, then |{:(logl, p, 1),(log m, q, 1),(log n ,r,1):}| equals :

If a,b,c are positive and ar the p^(th),q^(th),r^(th) terms respectively of a G.P show that, |{:(,log a,p,1),(,log b,q,1),(,log c,r,1):}|=0

If a,b,c are the p^(th),q^(th),r^(th) terms in H.P.then det[[ca,q,1ab,r,1]]=

Determine the 2^(nd) term and the r^(th) term of an A.P,whose 6^(th) term is 12 and 8 th term is 22

If the p^(th), q^(th) and r^(th) terms of a GP. Are again in G.P., then which one of the following is correct?

If the p^(th), q^(th) and r^(th) terms of a G.P are a,b,c respectively then the value of a^(q-r).b^(r-p).c^(p-q)=

NDA PREVIOUS YEARS-MATRICES & DETERMINANTS-MQS
  1. Which one of the following factors does the expansions of the determin...

    Text Solution

    |

  2. What is the adjoint of the matrix ({:(cos(-theta)-sin(-theta)),(-sin(-...

    Text Solution

    |

  3. If A and B are two invertible matrices of same order, the (AB)^-1 is (...

    Text Solution

    |

  4. If a+b+c=0, one root of |a-x c b c b-x a b a c-x|=0 is x=1 b. x=2 c. ...

    Text Solution

    |

  5. What should be the value of x so that the matrix ({:(2,4),(-8,x):}) d...

    Text Solution

    |

  6. The system of equation 2x + y - 3z = 5 3x-2y+2z=5 and 5x-3y-z=16

    Text Solution

    |

  7. If u, v and w (all positive) are the p^(th), q^(th) and r^(th) terms o...

    Text Solution

    |

  8. Consider the following in respect of matrices A, B and C of same order...

    Text Solution

    |

  9. Let matrix B be the adjoint of a square matrix A, l be the identity ma...

    Text Solution

    |

  10. What is the determinant of the matrix ({:(x,y,y+z),(z,x,z+x),(y,z,x+y)...

    Text Solution

    |

  11. If A, B and C are the angles of a triangle and |(1,1,1),(1 + sin A,1...

    Text Solution

    |

  12. Consider the following in respect of matrices A and B of same order : ...

    Text Solution

    |

  13. What is the area of the triangle with vertices (x(1),(1)/(x(1))),(x(2)...

    Text Solution

    |

  14. If B = [{:(3,2,0),(2,4,0),(1,1,0):}], then what is adjoint of B equal ...

    Text Solution

    |

  15. If A = [{:(0,1),(1,0):}], then the matrix A is/an

    Text Solution

    |

  16. If A is a identity matrix of order 3, then its inverse (A^(-1))

    Text Solution

    |

  17. A is a square matrix of order 3 such that its determinant is 4. What i...

    Text Solution

    |

  18. If A is square matrix of order n gt 1, then which one of the following...

    Text Solution

    |

  19. Let A and B be (3 xx 3) matrices with det A = 4 and det B = 3. What ...

    Text Solution

    |

  20. Let A and B be (3 xx 3) matrices with det A = 4 and det B = 3. What ...

    Text Solution

    |