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Homework Help: Limit of a function

  1. Jan 15, 2010 #1
    1. The problem statement, all variables and given/known data
    http://img23.imageshack.us/img23/9366/95631341.jpg [Broken]

    2. Relevant equations

    3. The attempt at a solution
    If the dot (-1,3) is gone, does the limit of x->-1 exist??
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Jan 15, 2010 #2


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    Homework Helper

    Re: Limit

    How do you conclude lim x->(-1)+ is 3? And why do you think lim x->(-1) doesn't exist?
  4. Jan 15, 2010 #3
    Re: Limit

    Yeah, you should check E and F
    you got f wrong because e is wrong
    for e, why did you say that the answer is 3
    if the question was f(-1) = ?, then the answer would be 3
  5. Jan 15, 2010 #4
    Re: Limit

    no.., just ignore the answer
    I know x->(-1)+ is 1
    but is x->(-1) exist ,if the dot is gone?
  6. Jan 15, 2010 #5


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    Re: Limit

    Yes. The limit as x goes to a from below or above, or the limit as x goes to a, all depend only on the values of f(x) for x close to a, not at a. The value of f(a) is irrelevant to [/math]\lim_{x\to a} f(x)[/math] which may exist even if f(a) does not exist.
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