Results 1 to 2 of 2

Math Help - Statements about the real number x

  1. #1
    Junior Member
    Joined
    Oct 2009
    Posts
    59

    Statements about the real number x

    Show that these statements about the real number x are equivalent: (i) x is rational, (ii) x/2 is rational, (iii) 3x-1 is rational.
    Last edited by mr fantastic; September 28th 2010 at 03:10 PM. Reason: Re-titled.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Oct 2009
    Posts
    5,536
    Thanks
    778
    Fill in ... in the following.

    Recall the definition: x is rational if there exist integers m and n such that n > 0 and ...

    Try proving (i) => (ii). Assume that x is rational. Then there exist m and n such that ... I need to show that x / 2 is rational. This means proving that there exist integers m' and n' such that x / 2 = ... Can I come up with such m' and n'?
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. The number of real solutions
    Posted in the Calculus Forum
    Replies: 2
    Last Post: March 5th 2011, 06:11 AM
  2. Not a real number
    Posted in the Algebra Forum
    Replies: 1
    Last Post: November 2nd 2009, 11:41 AM
  3. Real Number
    Posted in the Algebra Forum
    Replies: 2
    Last Post: January 6th 2009, 09:11 PM
  4. For all real number x
    Posted in the Algebra Forum
    Replies: 1
    Last Post: August 21st 2008, 11:15 AM
  5. Real number
    Posted in the Advanced Algebra Forum
    Replies: 1
    Last Post: March 13th 2008, 04:31 PM

Search Tags


/mathhelpforum @mathhelpforum