Finding the Supremum: Solving for the Least Upper Bound of a Function

[Ted123]

Homework Statement

What is

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

The Attempt at a Solution

How do I find the least upper bound?

 

[susskind_leon]

Think about it: If you have a function type h(x,y)=f(x)*g(y). How would you find its maximum?