Results 1 to 3 of 3

Math Help - Show that u is not part of analytic function

  1. #1
    Newbie
    Joined
    Oct 2009
    Posts
    24

    Show that u is not part of analytic function

    Show that u is not part of analytic function-phpoih2q3.png

    Answer
    u(x,y) is the real part of an analytic function if and only if:d^2u/dx^2 + d^2u/dy^2 = 0
    But for u(x,y) = x^2+y^2 we have:
    d^2u/dx^2 = 2
    and
    d^2u/dy^2 = 2
    Thus:
    d^2u/dx^2 + d^2u/dy^2 = 4 0 -> it's not the real part of an analytic function
    Is the answer correct.....
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Sep 2012
    From
    Australia
    Posts
    3,619
    Thanks
    592

    Re: Show that u is not part of analytic function

    Hey mathsforumhelp.

    Are you dealing with a complex function such that u(x,y) is real part and v(x,y) is complex part for an input z = x + iy?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Super Member
    Joined
    Sep 2012
    From
    Washington DC USA
    Posts
    525
    Thanks
    146

    Re: Show that u is not part of analytic function

    Yes, your answer and reasoning are correct. That suffices to prove that u can't be the real part of an analytic function (given the presumed meanings as chiro asked about).
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Show that u is the real part of analytic function
    Posted in the Advanced Math Topics Forum
    Replies: 1
    Last Post: October 16th 2012, 04:39 AM
  2. Find an analytic function from its real part
    Posted in the Differential Geometry Forum
    Replies: 1
    Last Post: September 23rd 2011, 04:17 PM
  3. Complex Analysis: Show exp|z| not analytic
    Posted in the Differential Geometry Forum
    Replies: 2
    Last Post: May 22nd 2010, 09:28 AM
  4. Show function satisties C-R relations, but is not analytic
    Posted in the Differential Geometry Forum
    Replies: 1
    Last Post: February 6th 2010, 05:10 PM
  5. Replies: 1
    Last Post: February 3rd 2010, 01:44 PM

Search Tags


/mathhelpforum @mathhelpforum