1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Prove the multivariable does not exist?

  1. Oct 27, 2013 #1
    1. I know both dne but how can i prove it? Im not getting any solid answers? help please!

    (x,y) to (0,0)
    1. ((x^2)y+x(y^2))/((x^2)-(y^2))
    2. (x+y)/((x^2)+y+(y^2))

    2. 1. Simplified down to xy/(x-y)
    2. Simplified down to x/(x^2+y^2+y) + 1/((y+1)+x^2)
  2. jcsd
  3. Oct 27, 2013 #2

    Ray Vickson

    User Avatar
    Science Advisor
    Homework Helper

    What would need to happen in order for xy/(x-y) to have a limit as (x,y) → (0,0)? Does that happen in this case?

    So, your very first step is to make sure you understand what is meant by a function going to a limit---if you do not understand that you are defeated right from the start.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted