Home
Class 11
MATHS
The first term of a G.P. is 1. The sum o...

The first term of a G.P. is 1. The sum of the third and fifth terms is 90. Find the common ratio of the G.P.

Text Solution

Verified by Experts

Now, a_3​+a_5​=90
`=>ar^2+ar^4=90`
`=>r^2+r^4=90`
`=>r^4+r^2−90=0`
...
Promotional Banner

Topper's Solved these Questions

  • FUNCTIONS

    RD SHARMA|Exercise Solved Examples And Exercises|157 Videos

  • GRAPHS OF TRIGONOMETRIC FUNCTIONS

    RD SHARMA|Exercise Solved Examples And Exercises|5 Videos

Similar Questions

Explore conceptually related problems

The first terms of a G.P.is 1. The sum of the third and fifth terms is 90. Find the common ratio of the G.P.

The first term of a G. P. is 1 . The sum of the third and fifth terms is 90 . Find the common ratio of G.P.

The first term of a G.P.is 1. The sum of the third term and fifth term is 90. Find the common ratio of G.P.

The first term of a GP is 1 and the sum of its 3rd and 5th terms is 90. Find the common ratio of the GP.

The sum of first three terms of a G.P. is (1)/(8) of the sum of the next three terms. Find the common ratio of G.P.

The sum of first three terms of a G.P. is 21 and sum of their squares is 189. Find the common ratio :

The third term of a G.P. is 2. Then product of the first five terms, is :

The sum of first 6 terms of a G.P. is nine times the sum of the first 3 terms. Find the common ratio.

RD SHARMA-GEOMETRIC PROGRESSIONS-Solved Examples And Exercises
  1. Find the 5th term of the progression 1,((sqrt(2)-1))/(2sqrt(3)),\ ((3-...

    Text Solution

    |

  2. Which term of the G.P. 5,10 ,20 ,40 , i s 5120 ?

    Text Solution

    |

  3. The first term of a G.P. is 1. The sum of the third and fifth terms is...

    Text Solution

    |

  4. If the 4th and 9th terms of a G.P. be 54 and 13122 respectively, fi...

    Text Solution

    |

  5. Find a G.P. for which sum of the first two terms is -4 and the fifth...

    Text Solution

    |

  6. (ii)If the third term of G.P.is 4, then find the product of first five...

    Text Solution

    |

  7. If the p t h ,\ q t h\ a n d\ r t h terms of a G.P. are a ,\ b ,\ c re...

    Text Solution

    |

  8. Find four numbers forming a geometric progression in which the third ...

    Text Solution

    |

  9. The number of bacteria in a certain culture doubles every hour. If ...

    Text Solution

    |

  10. What will Rs. 500 amounts to in 10 years after its deposit in a bank w...

    Text Solution

    |

  11. A manufacturer reckons that the value of a machine, which costs him Rs...

    Text Solution

    |

  12. If the first and the nth terms of a G.P., are aa n db , respectively, ...

    Text Solution

    |

  13. Show that the products of the corresponding terms o the sequences a ,\...

    Text Solution

    |

  14. If p^(t h),\ q^(t h),\ r^(t h)a n d\ s^(t h) terms of an A.P. are in G...

    Text Solution

    |

  15. Show that each of one of the following progression is a G.P. Also, fin...

    Text Solution

    |

  16. Show that each of one of the following progression is a G.P. Also, fin...

    Text Solution

    |

  17. Show that each of one of the following progression is a G.P. Also, ...

    Text Solution

    |

  18. Show that each of one of the following progression is a G.P. Also, ...

    Text Solution

    |

  19. Show that the sequence defined by an=2/(3^n),\ n in N\ is a G.P.

    Text Solution

    |

  20. Find: the ninth term of the G.P. 1,4,16,64,………

    Text Solution

    |