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!

Homework Help: Supremum problem

  1. Jan 26, 2012 #1
    1. The problem statement, all variables and given/known data

    What is

    [tex]\displaystyle \sup_{\substack{x\in [-1.7,1.4] \\ y\in\mathbb{R} }} \frac{2.6xy}{(y^2+1)^2}[/tex]
    (the supremum of [itex]\displaystyle \frac{2.6xy}{(y^2+1)^2}[/itex] over [itex]x\in [-1.7,1.4][/itex] and [itex]y\in\mathbb{R}[/itex])?

    3. The attempt at a solution

    How do I find the least upper bound?
    Last edited: Jan 26, 2012
  2. jcsd
  3. Jan 26, 2012 #2
    Re: Supremum

    Think about it: If you have a function type h(x,y)=f(x)*g(y). How would you find its maximum?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook