Home
Class 11
MATHS
The sum of 20 terms of a series of whi...

The sum of 20 terms of a series of which every even term is 2 times the term before it, every odd term is 3 times the term before it, the first term being unity is a. `(2/7)(6^(10)-1)` b. `(3/7)(6^(10)-1)` c.`(3/5)(6^(10)-1)` d. none of these

Text Solution

AI Generated Solution

Promotional Banner

Topper's Solved these Questions

  • RELATIONS AND FUNCTIONS

    CENGAGE ENGLISH|Exercise All Questions|9 Videos

  • STRAIGHT LINES

    CENGAGE ENGLISH|Exercise All Questions|491 Videos

Similar Questions

Explore conceptually related problems

Find the sum of 2n terms of the series whose every even term is ' a ' times the term before it and every odd term is ' c ' times the term before it, the first term being unity.

The sum of 10 terms of the series sqrt2 + sqrt6 + sqrt18 +... is

Find the sum of first 20 terms of an A.P., in which 3rd term is 7 and 7th term is two more than thrice of its 3rd term.

The first term of an infinite G.P. is 1 and every term is equals to the sum of the successive terms, then its fourth term will be

Find the sum of first 20 terms of an A.P., in which 3r d terms in 7 and 7t h term is tow more than thrice of its 3r d term.

If the sum of first two terms of an infinite G.P is 1 and every term is twice the sum of all the successive terms then its first term is

Find the G.P. whose 2nd term is 12 and 6th term is 27 times the 3rd term.

The sum of the first n terms of a series is 31, and the sum of the first n - 1 terms of the series is 20. What is the value of nth terms in the series?

In a GP the 3rd term is 24 and the 6th term is 192. Find the 10th term.

In a GP the 3rd term is 24 and the 6th term is 192. Find the 10th term.

CENGAGE ENGLISH-SEQUENCES AND SERIES-All Questions
  1. If a = underset(55 "times")underbrace(111.....1), b= 1+10+10^(2)+10^(3...

    Text Solution

    |

  2. Consider the ten numbers a r ,a r^2, a r^3, ..... ,a r^(10)dot If the...

    Text Solution

    |

  3. The sum of 20 terms of a series of which every even term is 2 times ...

    Text Solution

    |

  4. Let an be the nth term of a G.P. of positive numbers. Let sum(n=1)^(10...

    Text Solution

    |

  5. If the pth, qth, and rth terms of an A.P. are in G.P., then the common...

    Text Solution

    |

  6. In a G.P. the first, third, and fifth terms may be considered as the ...

    Text Solution

    |

  7. If a,b,c,d be in G.P. show that (b-c)^2+(c-a)^2+(d-b)^2=(a-d)^2.

    Text Solution

    |

  8. If the pth, qth, rth, and sth terms of an A.P. are in G.P., then p-q ,...

    Text Solution

    |

  9. A B C is a right-angled triangle in which /B=90^0 and B C=adot If n po...

    Text Solution

    |

  10. If (1-p)(1+3x+9x^2+27 x^3+81 x^4+243 x^5)=1-p^6,p!=1 , then the value ...

    Text Solution

    |

  11. ABCD is a square of length a, a in N, a > 1. Let L1, L2 , L3... be poi...

    Text Solution

    |

  12. Let Tr a n dSr be the rth term and sum up to rth term of a series, res...

    Text Solution

    |

  13. If (1+3+5++p)+(1+3+5++q)=(1+3+5++r) where each set of parentheses cont...

    Text Solution

    |

  14. If a x^3+b x^2+c x+d is divisible by a x^2+c ,t h e na ,b ,c ,d are in...

    Text Solution

    |

  15. The line x+ y = 1 meets X-axis at A and Y-axis at B,P is the mid-poin...

    Text Solution

    |

  16. In a geometric series, the first term is a and common ratio is rdot If...

    Text Solution

    |

  17. If x ,y ,a n dz are distinct prime numbers, then (a).x , y , a n dz ma...

    Text Solution

    |

  18. If x ,y , and z are in G.P. and x+3,y+3, and z+3 are in H.P., then y=2...

    Text Solution

    |

  19. If A.M., G.M., and H.M. of the first and last terms of the series of 1...

    Text Solution

    |

  20. The sum 1+3+7+15+31+...to100 terms is a. 2^(100)-102 b. 2^(99)-101 c...

    Text Solution

    |