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

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In summary, the supremum of a function is the smallest number that is greater than or equal to all of the values of the function. It can be found by finding the maximum value of the function or using calculus to find critical points. Finding the supremum is important for understanding the behavior and range of values of a function, as well as for optimization problems. A function can only have one supremum, but if there are multiple values equal to the least upper bound, they can all be considered supremum. The difference between supremum and maximum is that the maximum is the largest value of the function, while the supremum is the least upper bound and may be equal to or greater than the maximum.
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Homework Statement



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])?

The Attempt at a Solution



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

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

What is the supremum of a function?

The supremum of a function is the least upper bound of the function, meaning it is the smallest number that is greater than or equal to all the values of the function.

How do you find the supremum of a function?

To find the supremum of a function, you can use a variety of methods such as finding the maximum value of the function or using calculus to find the critical points and evaluating the function at those points.

Why is finding the supremum important?

Finding the supremum of a function can help in understanding the behavior of the function and its range of values. It is also useful in optimization problems where the goal is to find the maximum value of a function.

Can a function have more than one supremum?

No, a function can only have one supremum. If a function has multiple values that are equal to the least upper bound, then all of those values can be considered the supremum.

What is the difference between supremum and maximum?

The supremum of a function is the least upper bound, while the maximum is the largest value of the function. The maximum may not always exist, but the supremum always exists. Additionally, the supremum can be equal to the maximum, but it can also be greater than the maximum.

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