PlanetMath (more info)
 Math for the people, by the people. Sponsor PlanetMath
Encyclopedia | Requests | Forums | Docs | Wiki | Random | RSS  
Login
create new user
name:
pass:
forget your password?
Main Menu
Owner confidence rating: Very high Entry average rating: No information on entry rating
[parent] infimum and supremum of sum and product (Theorem)

Suppose that the real functions $f$ and $g$ are defined on an interval $\Delta$ . Then on this interval

  • $\inf(f\!+\!g) \;\geqq\; \inf f+\inf g$
  • $\sup(f\!+\!g) \;\leqq\; \sup f+\sup g$

If $f$ and $g$ are also nonnegative on $\Delta$ , we can write

  • $\inf(fg) \;\geqq\; \inf f\cdot\inf g$
  • $\sup(fg) \;\leqq\; \sup f\cdot\sup g$




"infimum and supremum of sum and product" is owned by pahio.
(view preamble | get metadata)

View style:

See Also: sum and product and quotient of functions


This object's parent.
Log in to rate this entry.
(view current ratings)

Cross-references: interval, real functions

This is version 1 of infimum and supremum of sum and product, born on 2009-09-03.
Object id is 11895, canonical name is InfimumAndSupremumOfSumAndProduct.
Accessed 502 times total.

Classification:
AMS MSC06A05 (Order, lattices, ordered algebraic structures :: Ordered sets :: Total order)
 26D15 (Real functions :: Inequalities :: Inequalities for sums, series and integrals)

Pending Errata and Addenda
None.
Discussion
Style: Expand: Order:
forum policy

No messages.

Interact
post | correct | update request | prove | add result | add corollary | add example | add (any)