Results 1 to 3 of 3

Math Help - Partial order relation: lub and glb

  1. #1
    Junior Member
    Joined
    Oct 2012
    From
    Wisconsin
    Posts
    29
    Thanks
    1

    Partial order relation: lub and glb

    I'm a little confused by this problem:

    Let D = {2, 3, 6, 8, 9, 10, 12, 15, 18, 20} and R is the partial order relation defined on D where a R b means a | b.

    Find the requested elements if they exist.

    1. The lub({3,10})
    2. The lub({2, 9})
    3. The glb({12, 10})

    My answers:
    1. lub({3,10}) does not exist.
    2. The lub({2, 9}) = 18.
    3. The glb({12, 10}) = 2.

    Am I doing this correctly? Any suggestions are welcome.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Senior Member jakncoke's Avatar
    Joined
    May 2010
    Posts
    387
    Thanks
    80

    Re: Partial order relation: lub and glb

    Yes. You are

    Basically, partial order also can be symbolically represented as  \leq So when it means, find the lub for a subset  A \subset B
    Basically find the smallest number  b \in B such that for any  a \in A  a \leq b such the  \leq represents division, this means find the smallest element in B which is divided by everything in A and glb means find the greatest element in B which divides every element in A. But you seem to know all this already since you did the problems right.
    Last edited by jakncoke; December 17th 2012 at 10:36 PM.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Oct 2012
    From
    Wisconsin
    Posts
    29
    Thanks
    1

    Re: Partial order relation: lub and glb

    Nice. Thanks.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Order Relation
    Posted in the Number Theory Forum
    Replies: 5
    Last Post: September 19th 2012, 05:52 AM
  2. 3rd Order Recurrence Relation
    Posted in the Discrete Math Forum
    Replies: 2
    Last Post: April 26th 2011, 03:44 AM
  3. Partial Order Relation help
    Posted in the Discrete Math Forum
    Replies: 1
    Last Post: February 11th 2011, 12:29 AM
  4. Partial Order relation and hasse diagram mxa/min
    Posted in the Discrete Math Forum
    Replies: 1
    Last Post: September 27th 2010, 11:02 PM
  5. Partial order relation
    Posted in the Discrete Math Forum
    Replies: 10
    Last Post: April 17th 2006, 01:34 PM

Search Tags


/mathhelpforum @mathhelpforum