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2.2: The Limit of a Function

  • Page ID
    143298
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    1. Sketch the graph of a function \(f(x)\) that is continuous at \(x = 1\) with \(\displaystyle \lim_{x \to 1} f(x) = -2\).
       
    2. Sketch the graph of a function \(g(x)\) that is discontinuous at \(x = 1\) with \(\displaystyle \lim_{x \to 1} g(x) = -2\).
       
    3. Sketch the graph of a function \(h(x)\) with \(\displaystyle \lim_{x \to -2^-} h(x) = 3\), \(\displaystyle \lim_{x \to -2^+} h(x) = 1\), and \(h(-2) = 3\).
       
    4. Sketch the graph of a function \(f(t)\) with \(\displaystyle \lim_{t \to 0} f(t) = -\infty\).
       
    5. Sketch the graph of a function \(g(t)\) with \(\displaystyle \lim_{t \to -1^-} g(t) = \infty\), \(\displaystyle \lim_{t \to -1^+} g(t) = 0\), and \(g(1) = 2\).
       
    6. Given only that \(\displaystyle \lim_{x \to 11} h(x) = 4\) for some function \(h(x)\), is it possible to calculate \(\displaystyle \lim_{x \to 11^-} h(x)\) and \(\displaystyle \lim_{x \to 11^+} h(x)\)? Briefly explain why or why not.
       
    7. Given only that \(\displaystyle \lim_{x \to 11} f(x) = 4\) for some function \(f(x)\), is it possible to calculate \(f(11)\)? Briefly explain why or why not.
       
    8. Given only that \(g(11) = 4\) for some function \(g(x)\), is it possible to calculate \(\displaystyle \lim_{x \to 11} g(x)\)? Briefly explain why or why not.
       
    9. Given only that \(h(11) = 4\) for some continuous function \(h(x)\), is it possible to calculate \(\displaystyle \lim_{x \to 11} h(x)\)? Briefly explain why or why not.
       
    10. Given only that \(\displaystyle \lim_{x \to 11^-} f(x) = 4\) and \(\displaystyle \lim_{x \to 11^+} f(x) = 4\) for some function \(f(x)\), is it possible to calculate \(\displaystyle \lim_{x \to 11} f(x)\)? Briefly explain why or why not.
       
    11. Given only that \(\displaystyle \lim_{x \to 11^-} f(x) = 5\) and \(\displaystyle \lim_{x \to 11^+} f(x) = 2\) for some function \(f(x)\), is it possible to calculate \(\displaystyle \lim_{x \to 11} f(x)\)? Briefly explain why or why not.
       
    12. Use a calculator to complete the table below for the function \(g(x) = 2x + 1\), then use your results to make inferences about \(\displaystyle \lim_{x \to -1^-} g(x)\), \(\displaystyle \lim_{x \to -1^+} g(x)\), and \(\displaystyle \lim_{x \to -1} g(x)\).
       
      \(x\) \(g(x)\)   \(x\) \(g(x)\)
      -1.01     -0.99  
      -1.001     -0.999  
      -1.0001     -0.9999  

       
    13. Use a calculator to complete the table below for the function \(h(x) = \dfrac{\sin(x)}{x}\), then use your results to make inferences about \(\displaystyle \lim_{x \to 0^-} h(x)\), \(\displaystyle \lim_{x \to 0^+} h(x)\), and \(\displaystyle \lim_{x \to 0} h(x)\).
       
      \(x\) \(h(x)\)   \(x\) \(h(x)\)
      -0.01     0.01  
      -0.001     0.001  
      -0.0001     0.0001  

       
    14. Use a calculator to complete the table below for the function \(f(x) = \dfrac{x^2-1)}{|x-1|}\), then use your results to make inferences about \(\displaystyle \lim_{x \to 1^-} f(x)\), \(\displaystyle \lim_{x \to 1^+} f(x)\), and \(\displaystyle \lim_{x \to 1} f(x)\).
       
      \(x\) \(f(x)\)   \(x\) \(f(x)\)
      0.99     1.01  
      0.999     1.001  
      0.9999     1.0001  

       
    15. Use a calculator to complete the table below for the function \(g(x) = (1+x)^{1/x}\), then use your results to make inferences about \(\displaystyle \lim_{x \to 0^-} g(x)\), \(\displaystyle \lim_{x \to 0^+} g(x)\), and \(\displaystyle \lim_{x \to 0} g(x)\).
       
      \(x\) \(g(x)\)   \(x\) \(g(x)\)
      -0.01     0.01  
      -0.001     0.001  
      -0.0001     0.0001  

       
    16. Use a calculator to complete the table below for the function \(h(x) = \dfrac{x+1}{x-2}\), then use your results to make inferences about \(\displaystyle \lim_{x \to 2^-} h(x)\), \(\displaystyle \lim_{x \to 2^+} h(x)\), and \(\displaystyle \lim_{x \to 2} h(x)\).
       
      \(x\) \(h(x)\)   \(x\) \(h(x)\)
      1.99     2.01  
      1.999     2.001  
      1.9999     2.0001  

    2.2: The Limit of a Function is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.

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