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A few limit questions.

  1. Oct 10, 2011 #1
    1. The problem statement, all variables and given/known data
    Hello. I have a few questions I wanted to run by just to make sure I did them right.

    all the below have lim (x,y) -> (0,0)

    1) [​IMG]

    2) [​IMG]



    2. Relevant equations



    3. The attempt at a solution

    ok so this is what i did for the following.

    1) if i approach from the x axis and y axis, both the limits give me -3/0 as an answer. If i approach from y = ax, i also get -3/0 as the final answer. So the limit does not exist? What other methods can i use here because I'm not sure if this is right.

    2) approaching from the y-axis I get lim y-> 0 of y^2/y^2 = 1
    approaching from the x-axis i get lim x-> 0 3x^2/x^2 = 3
    since those two aren't equal I can conclude that the limit does not exist.
     
    Last edited: Oct 10, 2011
  2. jcsd
  3. Oct 10, 2011 #2

    SammyS

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    Andre,

    Welcome to PF.

    You will get better response if you post only one or two problems per thread. (That's also in the Forum Rules.)

    For (1):

    You might still want to see if the limit is +∞ or if it's -∞ -- or just plain DOES NOT EXIST. Check that along the y-axis from the positive versus the negative direction.

    For (2):

    That's correct.

    For (3):

    Also correct.
     
  4. Oct 10, 2011 #3
    Thanks for the reply. I edited my post to have 2 questions only. Thanks!
     
  5. Oct 10, 2011 #4

    SammyS

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    Post the other two in another thread
     
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