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Quick question

  1. May 27, 2008 #1
    k(x) is a continuous function. k(x)=-1 and k(4)=2 then is this statement true:

    lim x->3- k(x) = lim x->3+ k(x)


    i realli hv no idea. could sumone help me please?
     
  2. jcsd
  3. May 27, 2008 #2

    Dick

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    What does continuous mean in terms of limits? k(x)=(-1) means the function is constant. k(4)=2 contradicts the previous statement. What's the real problem?
     
  4. May 27, 2008 #3
    sorry i typed the question wrong k(3)=-1
     
  5. May 27, 2008 #4

    Dick

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    S'ok. But the question is still odd, because the values of the function don't have anything to do with whether the two limits are equal. If a function is continuous at x=3, what can you say about it's left and right hand limits? Do you mean to say k(x) is only defined on the interval [3,4]? Or is it defined and continuous everywhere?
     
  6. May 27, 2008 #5
    k(x) is continuous for all real numbers
     
  7. May 27, 2008 #6

    Dick

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    Fine. Then the values of the function have nothing to do with the problem. What does being continuous tell you about limits?
     
  8. May 27, 2008 #7
    umm im not exactly sure but the left hand limit should equal the right hand limit?
     
  9. May 27, 2008 #8

    Dick

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    Pretty much. And they both should equal the value of the function at x=3. Kind of a silly question then, yes?
     
  10. May 27, 2008 #9
    yes lol but thank you so much for ur help. it helped cleared things up for me.
     
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