Results 1 to 4 of 4

Math Help - scatch the graph

  1. #1
    Newbie
    Joined
    Mar 2009
    Posts
    20

    scatch the graph

    Hello,

    I need help with the analysis of the following function.
    Before to draw it need to find intersection points, min. max. asymptotes, discuss the domain, convexity/concavity by the usage of the second derivative test.. Having difficuloties with the following function:
    f= x^x

    and

    f=e^(-x^2)

    any help is welcome.

    Thanks,
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor Calculus26's Avatar
    Joined
    Mar 2009
    From
    Florida
    Posts
    1,271
    f = x^x = e^(xln(x))

    f' = e^(xln(x))(ln(x)+1)

    f' = x^x(ln(x)+1)

    I'll let you take it from here
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Mar 2009
    Posts
    20
    thank you,
    but the problem for me is to define the functions find D.O (is it defined for the negative numbers?), more is the limit of x^x when x approaches zero 1 ? and what is is zero when x approaches -infinity ??
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor Calculus26's Avatar
    Joined
    Mar 2009
    From
    Florida
    Posts
    1,271
    x^x is only defined for x> 0 so it makes no sense in talking asbout the limit
    as x goes to - infinity since x is never negative


    You would have to know L Hopital's rule in order to show x^x->1 as
    x ->0 :

    write y = lim (x^x)
    x ->0
    lny = lim xln(x)
    x->0

    lim xln(x) = lim ln(x)/(1/x) = lim -x = 0

    lny = 0

    y = e^0 = 1

    i.e lim x^x = 1 as x goes to 0

    Without L'hopital's rule you'll have to rely on a graph
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Graph Theory / Chromatic Number of a Complete Graph
    Posted in the Discrete Math Forum
    Replies: 1
    Last Post: November 15th 2011, 09:59 AM
  2. Replies: 7
    Last Post: August 5th 2011, 01:30 PM
  3. Replies: 0
    Last Post: September 25th 2010, 05:59 AM
  4. Graph Theory - Size of a Line Graph
    Posted in the Discrete Math Forum
    Replies: 1
    Last Post: July 25th 2010, 11:15 PM
  5. Replies: 1
    Last Post: February 15th 2009, 05:35 AM

Search Tags


/mathhelpforum @mathhelpforum