Results 1 to 3 of 3

Math Help - Finding a value of an expression

  1. #1
    Junior Member lanierms's Avatar
    Joined
    May 2010
    From
    Seoul, South Korea
    Posts
    50

    Finding a value of an expression

    a, b, x, y are real numbers.
    When they satisfy the equations ax+by=3, ax^2+by^2=5, ax^3+by^3=9, ax^4+by^4=17, find the value of ax^5+by^5.

    Please help!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor

    Joined
    Apr 2005
    Posts
    15,393
    Thanks
    1327
    I think I would be inclined to "cheat". Notice that 5- 3= 2, 9- 5= 4, and 17- 9= 8. If that pattern continues, the next number would be 17+ 16= 33.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member lanierms's Avatar
    Joined
    May 2010
    From
    Seoul, South Korea
    Posts
    50
    Yeah, but how would you prove that?
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Finding a value of an expression
    Posted in the Pre-Calculus Forum
    Replies: 3
    Last Post: February 27th 2011, 05:40 PM
  2. Help Finding equivalent expression
    Posted in the Algebra Forum
    Replies: 11
    Last Post: November 26th 2009, 04:29 AM
  3. Finding lim(x->2) of following expression
    Posted in the Calculus Forum
    Replies: 9
    Last Post: August 26th 2009, 03:56 AM
  4. Finding an Expression
    Posted in the Math Topics Forum
    Replies: 2
    Last Post: November 9th 2008, 01:22 PM
  5. finding expression
    Posted in the Calculus Forum
    Replies: 4
    Last Post: August 6th 2006, 07:49 AM

Search Tags


/mathhelpforum @mathhelpforum