1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Need help

  1. Oct 7, 2004 #1
    Find all positive integers c such that it is possible to write c = a/b + b/a with positive integers a and b.
    Please help me :smile:
    Last edited: Oct 7, 2004
  2. jcsd
  3. Oct 7, 2004 #2


    User Avatar
    Science Advisor
    Homework Helper

    You know [tex]c=\frac{a^2+b^2}{ab}[/tex] is an integer, so [tex]ab[/tex] divides [tex]a^2+b^2[/tex]. What factors must a and b have in common?
  4. Oct 7, 2004 #3
    i got c=2 as the answer, is it right?
    Last edited: Oct 7, 2004
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook