Results 1 to 6 of 6

Math Help - why they chose maximum and not minimum functions..

  1. #1
    MHF Contributor
    Joined
    Nov 2008
    Posts
    1,401

    why they chose maximum and not minimum functions..

    in every example in this article
    it uses minimum function because we need to squeeze the function
    as close as possible to the limit(example 4).
    http://www.mathhelpforum.com/math-he...ta-proofs.html



    but i got this proove that use maximum.
    http://img440.imageshack.us/img440/9160/25023372lz4.gif

    why?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor Mathstud28's Avatar
    Joined
    Mar 2008
    From
    Pennsylvania
    Posts
    3,641
    Quote Originally Posted by transgalactic View Post
    in every example in this article
    it uses minimum function because we need to squeeze the function
    as close as possible to the limit(example 4).
    http://www.mathhelpforum.com/math-he...ta-proofs.html



    but i got this proove that use maximum.
    http://img440.imageshack.us/img440/9160/25023372lz4.gif

    why?
    Im sorry, maybe it is just my computer but I cannot see the majority of the paper. It might serve you better to start posting in LaTeX. From what I can see seems as though you have a case where you have two inequalities and you want them both to be true, so if x<m and y<n then if I have a function that is sometimes x and sometimes y then the only thing we can say the function is always less than is \max\left\{x,y\right\}.

    For example, suppose that g(x)<M and h(x)<N then the function f:x\longmapsto\left\{\begin{array}{rcl} h(x) & \mbox{if} & x\in\mathbb{Q}\\ g(x) & \mbox{if} & x\not\in\mathbb{Q}\end{array}\right. then on any interval we can really only say that f<\max\left\{M,N\right\}.

    Does that answer your question?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor
    Joined
    Nov 2008
    Posts
    1,401
    then why in the article they use minimum function?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor

    Joined
    Apr 2005
    Posts
    15,528
    Thanks
    1387
    Quote Originally Posted by transgalactic View Post
    then why in the article they use minimum function?
    In one they are working with |x-a| in the other they are looking at \frac{1}{|x-a|}. The reciprocal swaps "max" and "min".
    Follow Math Help Forum on Facebook and Google+

  5. #5
    MHF Contributor
    Joined
    Nov 2008
    Posts
    1,401
    i understand the because its 1/(expression) then it flips

    why in the first we choose min(the contained bound,epsilon/contained bound)

    ??
    Follow Math Help Forum on Facebook and Google+

  6. #6
    MHF Contributor
    Joined
    Nov 2008
    Posts
    1,401
    in the third example of the article we do not use 1/|x-a| expression

    so why they use min and not max ??
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 3
    Last Post: April 5th 2011, 06:43 PM
  2. Replies: 3
    Last Post: November 11th 2008, 10:12 PM
  3. maximum and minimum of functions
    Posted in the Calculus Forum
    Replies: 3
    Last Post: July 2nd 2008, 11:14 AM
  4. maximum and minimum of functions
    Posted in the Calculus Forum
    Replies: 2
    Last Post: July 1st 2008, 05:39 AM
  5. Maximum and minimum functions
    Posted in the Calculus Forum
    Replies: 2
    Last Post: June 24th 2008, 05:47 AM

Search Tags


/mathhelpforum @mathhelpforum