Inequality proof involving Infs and Sups

In summary, to prove that inf{f(x):x belongs to S} <= inf{g(x):x belongs to S}, we can use contradiction by assuming that there is a value of x where g(x) is less than the inf of all possible f(x)'s. This can be shown to be illogical and therefore proves the original statement.
  • #1
homegrown898
16
0

Homework Statement


Let F and G be bounded functions on S. If f(x) <= g(x) for all x in S prove that inf{f(x):x belongs to S} <= inf{g(x):x belongs to S}


Homework Equations


None

The Attempt at a Solution


Basically the idea is to let L0 = inf{f(x):x belongs to S} and L1 = inf{g(x):x belongs to S} and show that L0 <=L1
 
Physics news on Phys.org
  • #2
I suggest contradiction. Assume there is some value of x where g(x) is less than the inf of all possible f(x)'s, then see if you can show why that just don't make no sense.
 

What is the concept of "Inequality proof involving Infs and Sups"?

"Inequality proof involving Infs and Sups" is a mathematical concept used to show that one value is less than or equal to another value. It involves using the concepts of infimum (inf) and supremum (sup) to compare and prove inequalities between two sets of numbers.

What is an infimum and supremum?

An infimum is the greatest lower bound of a set of numbers, while a supremum is the smallest upper bound of a set of numbers. In other words, the infimum is the largest number that is less than or equal to all numbers in the set, and the supremum is the smallest number that is greater than or equal to all numbers in the set.

How are infimum and supremum used in inequality proofs?

Inequality proofs involving infimum and supremum use the properties of these concepts to show that one set of numbers is less than or equal to another set of numbers. This is done by comparing the infimum and supremum of each set and using mathematical operations to prove the inequality statement.

What are some common properties used in inequality proofs involving infimum and supremum?

Some common properties used in inequality proofs involving infimum and supremum include the monotonicity property (if a ≤ b, then c + a ≤ c + b), the transitivity property (if a ≤ b and b ≤ c, then a ≤ c), and the additivity property (if a ≤ b and c ≤ d, then a + c ≤ b + d).

How can one apply "Inequality proof involving Infs and Sups" in real-world situations?

"Inequality proof involving Infs and Sups" can be applied in various fields such as economics, statistics, and engineering to compare and analyze data sets. For example, in economics, infimum and supremum can be used to determine the minimum and maximum values of a set of prices, while in engineering, these concepts can be used to determine the upper and lower limits of a measurement.

Similar threads

  • Calculus and Beyond Homework Help
Replies
4
Views
247
  • Calculus and Beyond Homework Help
Replies
1
Views
285
  • Calculus and Beyond Homework Help
Replies
1
Views
460
  • Calculus and Beyond Homework Help
Replies
3
Views
521
  • Calculus and Beyond Homework Help
Replies
11
Views
2K
Replies
4
Views
1K
  • Calculus and Beyond Homework Help
Replies
1
Views
505
  • Calculus and Beyond Homework Help
Replies
3
Views
1K
  • Calculus and Beyond Homework Help
Replies
2
Views
912
  • Calculus and Beyond Homework Help
Replies
5
Views
2K
Back
Top