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Homework Help: Tolerance of a limit

  1. Sep 28, 2011 #1
    1. The problem statement, all variables and given/known data

    Consider f(x)=x^2.5. Note that limf(x) as x->0+ =0. The input must be less than ___ from 0 to guarantee the output is within 0.1 of the limit.

    2. Relevant equations

    N/A

    3. The attempt at a solution
     
  2. jcsd
  3. Sep 28, 2011 #2

    SammyS

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    What have you tried?

    Where are you stuck ?
     
  4. Sep 28, 2011 #3
    If I'm correct, the output can be 0.1 and -0.1. So I have computed:
    f(0.1)= 0.00316 and f(-0.1)= -0.00316
    These are the inputs that guarantee the output to be within 0.1 of the limit, 0. However, I think there is an error in my thinking somewhere.
     
  5. Sep 28, 2011 #4

    SammyS

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    You used 0.1 as an input.

    Solve f(x-0) = 0 + 0.1 for x.
     
  6. Sep 28, 2011 #5
    Ohhh okay! Got it. Thank you so much.
     
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