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Epsilon-Delta Problem

  1. Feb 9, 2012 #1
    Please Delete, Problem Solved

    Please Delete, Problem Solved
    Last edited: Feb 9, 2012
  2. jcsd
  3. Feb 9, 2012 #2


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    What is the limit of sin(5x)/x as x goes to 0? Taking "A" as that value you want to find x such that |sin(x)/x- A|< 0.01.
  4. Feb 9, 2012 #3
    The limit as sin(5x)/x goes to 0 is 5, right?
  5. Feb 9, 2012 #4


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    as a practical matter you may want to find t such that:

    |sin(t)/t - 1| < 0.01

    then use x = t/5.

    finding such a t (and thus x) isn't that hard (i did it by trial-and-error in about 2 minutes), the real trick is showing the inequality holds in the interval (-x,x). unless i am mistaken, the problem doesn't ask you to find the largest possible such x, just one that works.
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