Home
Class 11
MATHS
If the sum of the first n terms of a seq...

If the sum of the first n terms of a sequence is `2(7^(n)-1)//3` show that it is a G.P. Also , find its first term and common ratio.

Promotional Banner

Topper's Solved these Questions

  • SEQUENCES AND SERIES

    MARVEL PUBLICATION|Exercise MULTIPLE CHOICE QUESTIONS|81 Videos

  • QUESTION PAPER 2018

    MARVEL PUBLICATION|Exercise QUESTION|50 Videos

  • SETS, RELATIONS AND FUNCTIONS

    MARVEL PUBLICATION|Exercise MCQs|139 Videos

Similar Questions

Explore conceptually related problems

The nth term of a progression is 3^(n+1) . Show that it is a G.P. Also find its 5th term.

The nth term of a sequence is given by a_(n)=2n+7 .Show that it is an A.P.Also,find its 7 th term.

if for a sequence t_(n)=((-5)^(n+1))/(3^(n-1)) show that the sequence is a GP then find first term and common ratio.

Show that the sequence given by T_(n)=(2xx3^(n)) for all n in N is a GP. Find its first term and the common ratio.

The sum of n terms of a progression is (2^(n)-1) . Show that it is a GP and find its common ratio.

The nth term of a progression is 2^(n). Prove that it is G.P. Also find its common ratio.

Show that the sequence given by a_(n)3(2^(n)), for all n in N, is a G.P.Also find its common ratio.

If the sum of an infinite G.P. be 3 and the sum of the squares of its term is also 3, then its first term and common ratio are

If the sum of the first n terms of an AP is given by S_n=3n^2-n then find its nth terms, first term and common difference

If the sum of the first n terms of an A.P.is (1)/(2)(3n^(2)+7n), then find its nth term.Hence write its 20 th term.

MARVEL PUBLICATION-SEQUENCES AND SERIES -MULTIPLE CHOICE QUESTIONS
  1. If the sum of the first n terms of a sequence is 2(7^(n)-1)//3 show th...

    Text Solution

    |

  2. If for a G.P., a=8 and t(4)=64 then : r =

    Text Solution

    |

  3. If for a G.P., r=2 and t(9)=128, then : a =

    Text Solution

    |

  4. If, for a G.P., t(3) =0.08 and t(7) =0.000128, then : (a,r) -=

    Text Solution

    |

  5. If for a G.P., S(2) =8 and S(4)=80 , then : (a,r) -=

    Text Solution

    |

  6. If for a G.P., r=2 and S(8)=510, then : t(3) =

    Text Solution

    |

  7. If for a G.P., t(3)=36 and t(6)=972, then : t(8) =

    Text Solution

    |

  8. If for a G.P. , t(8) :t(3) =32 and S(9)=255, then : t(1)=

    Text Solution

    |

  9. If for a G.P., S(3) : S(6) =125 : 152 then : r =

    Text Solution

    |

  10. If for a G.P., a=5, r=2 and S(n) =635 then : n =

    Text Solution

    |

  11. If the n^(th) term of a G.P. is 3 (4^(n+1)) then its first term and co...

    Text Solution

    |

  12. If 2+x, 3+x, 9+x are in a G.P., then : x =

    Text Solution

    |

  13. If the positive numbers 3,x,5,y are in a G.P., then : (x,y)=

    Text Solution

    |

  14. Four number in G.P. such that the product of their extremes is 108 and...

    Text Solution

    |

  15. Three given numbers whose sum is 24 are in an A.P. If the first is dec...

    Text Solution

    |

  16. Three numbers whose sum is 18 are in AP if 2,4, 11 are added to them r...

    Text Solution

    |

  17. If the 5^(th) and 8^(th) terms of a G.P. are 32 and 256 respectively ....

    Text Solution

    |

  18. If 5^(th) , 8^(th) and 11^(th) terms of a G.P. are p,q and s respectiv...

    Text Solution

    |

  19. If x,y,z are in G.P. then log x , log y, logz, are in

    Text Solution

    |

  20. If the third term of G.P.is 4, then find the product of first five ter...

    Text Solution

    |

  21. If x, 2x+ 2, 3x + 3 are in G.P. , then the fourth term is

    Text Solution

    |