Home
Class 12
MATHS
Consider an AP with a as the first term ...

Consider an AP with a as the first term and d is the common difference such that `S_(n)` denotes the sum to n terms and `a_(n)` denotes the nth term of the AP. Given that for some m,`n inN,(S_(m))/(S_(n))=(m^(2))/(n^(2))(nen)`.
Statement 1 `d=2a` because
Statement 2 `(a_(m))/(a_(n))=(2m+1)/(2n+1)`.

A

Statement 1 is true, Statement 2 is true, Statement 2 is a corrct explanation for Statement 1.

B

Statement 1 is true, Statement 2 is true, Statement 2 is not a correct explanation for Statement 1.

C

Statement 1 is true, Statement 2 is false.

D

Statement 1 is false, Statement 2 is true.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze the given information about the arithmetic progression (AP) and the statements provided. ### Step-by-Step Solution: 1. **Understanding the Given Ratio**: We are given that: \[ \frac{S_m}{S_n} = \frac{m^2}{n^2} \] where \( S_n \) is the sum of the first \( n \) terms of the AP. 2. **Formula for the Sum of an AP**: The sum of the first \( n \) terms of an AP can be expressed as: \[ S_n = \frac{n}{2} \left(2a + (n-1)d\right) \] where \( a \) is the first term and \( d \) is the common difference. 3. **Expressing \( S_m \) and \( S_n \)**: Using the formula for the sum of an AP, we can write: \[ S_m = \frac{m}{2} \left(2a + (m-1)d\right) \] \[ S_n = \frac{n}{2} \left(2a + (n-1)d\right) \] 4. **Setting Up the Ratio**: Plugging these into the ratio gives: \[ \frac{S_m}{S_n} = \frac{\frac{m}{2} \left(2a + (m-1)d\right)}{\frac{n}{2} \left(2a + (n-1)d\right)} = \frac{m(2a + (m-1)d)}{n(2a + (n-1)d)} \] Setting this equal to \( \frac{m^2}{n^2} \): \[ \frac{m(2a + (m-1)d)}{n(2a + (n-1)d)} = \frac{m^2}{n^2} \] 5. **Cross Multiplying**: Cross multiplying gives: \[ m(2a + (m-1)d) \cdot n^2 = n(2a + (n-1)d) \cdot m^2 \] 6. **Analyzing the Statements**: - **Statement 1**: \( d = 2a \) - **Statement 2**: \( \frac{a_m}{a_n} = \frac{2m+1}{2n+1} \) 7. **Finding \( a_m \) and \( a_n \)**: The \( m \)-th term of the AP is given by: \[ a_m = a + (m-1)d \] The \( n \)-th term is: \[ a_n = a + (n-1)d \] 8. **Substituting for \( d \)**: If we assume \( d = 2a \), then: \[ a_m = a + (m-1)(2a) = a + 2am - 2a = 2am - a \] \[ a_n = a + (n-1)(2a) = a + 2an - 2a = 2an - a \] 9. **Finding the Ratio**: Now, substituting these into the ratio: \[ \frac{a_m}{a_n} = \frac{2am - a}{2an - a} = \frac{2m - 1}{2n - 1} \] This does not match Statement 2, which claims: \[ \frac{a_m}{a_n} = \frac{2m + 1}{2n + 1} \] Therefore, Statement 2 is false. 10. **Conclusion**: Since we have shown that \( d = 2a \) holds true, Statement 1 is true, and Statement 2 is false. ### Final Answer: - **Statement 1**: True - **Statement 2**: False

To solve the problem, we need to analyze the given information about the arithmetic progression (AP) and the statements provided. ### Step-by-Step Solution: 1. **Understanding the Given Ratio**: We are given that: \[ \frac{S_m}{S_n} = \frac{m^2}{n^2} ...
Promotional Banner

Topper's Solved these Questions

  • SEQUENCES AND SERIES

    ARIHANT MATHS ENGLISH|Exercise Exercise For Session 1|5 Videos
  • SEQUENCES AND SERIES

    ARIHANT MATHS ENGLISH|Exercise Exercise For Session 2|11 Videos
  • PROPERTIES AND SOLUTION OF TRIANGLES

    ARIHANT MATHS ENGLISH|Exercise Exercise (Questions Asked In Previous 13 Years Exam)|21 Videos
  • SETS, RELATIONS AND FUNCTIONS

    ARIHANT MATHS ENGLISH|Exercise Exercise (Questions Asked In Previous 13 Years Exam)|12 Videos

Similar Questions

Explore conceptually related problems

In an A.P. given that the first term (a) = 54, the common difference (d) = -3 and the n^(th) term (a_(n))=0 , find n and the sum of first n terms (S_(n)) of the A.P.

If S_n , denotes the sum of n terms of an AP, then the value of (S_(2n)-S_n) is equal to

Let there be an A.P. with first term ' a ' , common difference ' d ' . If a_n denotes its n t h term and S_n the sum of first n terms, find d , if a=3,\ \ n=8 and S_n=192 .

Let there be an A.P. with first term ' a ' , common difference ' d ' . If a_n denotes its n t h term and S_n the sum of first n terms, find n and a , if a_n=4,\ \ d=2 and S_n=-14 .

Let there be an A.P. with first term ' a ' , common difference ' d ' . If a_n denotes its n t h term and S_n the sum of first n terms, find n and a_n , if a=2,\ \ d=8 and S_n=90 .

Let there be an A.P. with first term ' a ' , common difference ' d ' . If a_n denotes its n t h term and S_n the sum of first n terms, find n and S_n , if a=5,\ \ d=3 and a_n=50

Let S_n denote the sum of first n terms of an A.P. and S_2n = 3S_n then ratio of S_3n : S_n

If S_(n) denotes the sum of first n terms of an AP, then prove that S_(12)=3(S_(8)-S_(4)).

If S_n denotes the sum of first n terms of an arithmetic progression and an denotes the n^(th) term of the same A.P. given S_n = n^2p ; where p,n in N , then

Consider an A.P. with first term 'a'. Let S_(n) denote the sum its terms. If (S_(kx))/(S_(x)) is independent of x, then S_(n)=

ARIHANT MATHS ENGLISH-SEQUENCES AND SERIES-Exercise (Questions Asked In Previous 13 Years Exam)
  1. Consider an AP with a as the first term and d is the common difference...

    Text Solution

    |

  2. Let a,b,c be in A.P. and |a|lt1,|b|lt1|c|lt1.ifx=1+a+a^(2)+ . . . ."to...

    Text Solution

    |

  3. about to only mathematics

    Text Solution

    |

  4. If a1, a2, a3, be terms of an A.P. and (a1+a2+.....+ap)/(a1+a2+.....+...

    Text Solution

    |

  5. If a1, a2, a3,.....an are in H.P. and a1 a2+a2 a3+a3 a4+.......a(n-1...

    Text Solution

    |

  6. Let V(r ) denotes the sum of the first r terms of an arithmetic progre...

    Text Solution

    |

  7. Let Vr denote the sum of the first r terms of an arithmetic progressio...

    Text Solution

    |

  8. Let V(r) denote the sum of the first r terms of an arithmetic progress...

    Text Solution

    |

  9. LetA(1),G(1),H(1) denote the arithmetic, geometric and harmonic means ...

    Text Solution

    |

  10. Let A1 , G1, H1denote the arithmetic, geometric and harmonic means re...

    Text Solution

    |

  11. LetA(1),G(1),H(1) denote the arithmetic, geometric and harmonic means ...

    Text Solution

    |

  12. In a G.P of positive terms if any term is equal to the sum of the next...

    Text Solution

    |

  13. Suppose four distinct positive numbers a(1),a(2),a(3),a(4) are in G.P....

    Text Solution

    |

  14. The first two terms of a geometric progression add up to 12. The sum o...

    Text Solution

    |

  15. If the sum of first n terms of an A.P. is cn^(2) then the sum of squar...

    Text Solution

    |

  16. The sum to infinity of the series 1+2/3+6/3^2+14/3^4+...is

    Text Solution

    |

  17. Let Sk,k=1, 2, …. 100 denote the sum of the infinite geometric series ...

    Text Solution

    |

  18. Let a1, a2, a3, ,a(11) be real numbers satisfying a1=15 , 27-2a2>0 a ...

    Text Solution

    |

  19. A person is to count 4500 currency notes. Let an denote the number of ...

    Text Solution

    |

  20. The minimum value of the sum of real numbers a^-5, a^-4, 3a^-3, 1,a^8 ...

    Text Solution

    |

  21. A man saves ₹ 200 in each of the first three months of his servies.In ...

    Text Solution

    |