Results 1 to 6 of 6
Like Tree1Thanks
  • 1 Post By Plato

Math Help - Arithmetic Series

  1. #1
    Junior Member
    Joined
    Jan 2013
    From
    Washington State
    Posts
    27

    Arithmetic Series

    The terms -2, 1+2k, 4+4k... form an arithmetic sequence. If the sum of the first ten terms is a+bk then give the value of a-b.

    I got up to finding the common difference (2k+3). I don't know what to do after.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Junior Member
    Joined
    Jun 2013
    From
    india
    Posts
    34
    Thanks
    5

    Re: Arithmetic Series

    sum upto 10 terms will be of the form of c+dk
    acc. to question S10=a+bk
    can u calculate the value of a and b??
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Super Member
    Joined
    Jul 2012
    From
    INDIA
    Posts
    829
    Thanks
    209

    Re: Arithmetic Series

    firstly the the three ters given are not in ap because [( 4+4k) - ( 1 + 2k)] is not equal to [ ( 1+2k)-(-2)]
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor

    Joined
    Aug 2006
    Posts
    18,712
    Thanks
    1641
    Awards
    1

    Re: Arithmetic Series

    Quote Originally Posted by ibdutt View Post
    firstly the the three ters given are not in ap because [( 4+4k) - ( 1 + 2k)] is not equal to [ ( 1+2k)-(-2)]
    What do you mean? (4+4k)-(1+2k)=3+2k=(1+2k)-(-2)
    Thanks from topsquark
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Super Member
    Joined
    Jul 2012
    From
    INDIA
    Posts
    829
    Thanks
    209

    Re: Arithmetic Series

    I regret this post is wrong the given terms are in AP with common difference 2k+3. But with three variables a,b and k we need to have some more information to resolve the solution.
    Last edited by ibdutt; June 23rd 2013 at 08:18 PM.
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Forum Admin topsquark's Avatar
    Joined
    Jan 2006
    From
    Wellsville, NY
    Posts
    9,966
    Thanks
    350
    Awards
    1

    Re: Arithmetic Series

    Okay, let me try this again. Your sum will have a k in it. After all, we are given that the sum is of the form a + bk...

    -Dan
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 3
    Last Post: November 14th 2012, 12:36 PM
  2. Replies: 2
    Last Post: May 22nd 2012, 05:57 AM
  3. Sum of the arithmetic series
    Posted in the Algebra Forum
    Replies: 2
    Last Post: July 6th 2011, 05:40 AM
  4. Arithmetic Progression or Arithmetic Series Problem
    Posted in the Math Topics Forum
    Replies: 1
    Last Post: October 8th 2009, 12:36 AM
  5. arithmetic series help
    Posted in the Algebra Forum
    Replies: 1
    Last Post: December 4th 2008, 11:44 AM

Search Tags


/mathhelpforum @mathhelpforum