Prove Limit Using Epsilon-delta Definition...3

Discussion in 'Calculus' started by nycmathguy, May 7, 2022.

  1. nycmathguy

    nycmathguy

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    Calculus
    Section 2.4

    I don't need to know this stuff to succeed in Calculus. However, I would like to have your math work reply file away as future study notes and/or reference notes. How about working out 28?

    Screenshot_20220507-174246_Samsung Notes.jpg
     
    nycmathguy, May 7, 2022
    #1
  2. nycmathguy

    MathLover1

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    28.

    lim((6+x)^(1/8),x->-6^+)=0

    want to find delta so that when |x-(-6)|< delta, |(6+x)^(1/8)-(-6)|<ϵ

    |x+6|< delta, |(6+x)^(1/8)+6|<ϵ

    start here
    |(6+x)^(1/8)+6|<ϵ
    ϵ>|(x + 6)^(1/8) + 6|

    proof:

    suppose ϵ>0 is given
    choose δ = ϵ=|(x + 6)^(1/8) + 6|
    δ = |(x + 6)^(1/8) + 6|

    assume δ <ϵ

    |x+6|<|(x + 6)^(1/8) + 6|

    -6<=x<1.28168

    so,

    x = -6, δ>0, ϵ>|(x + 6)^(1/8) + 6|
     
    MathLover1, May 8, 2022
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  3. nycmathguy

    nycmathguy

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    Lord Jesus, this Epsilon-delta stuff is not sinking into my brain. Are you willing to do a few more for me to study when time allows? Thank God I don't have to do know this stuff to learn calculus as a whole. I need you to break down each step with words from start to finish. Also, no further questions will be posted today because there are 3 unanswered threads in the Calculus forum.
     
    nycmathguy, May 8, 2022
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  4. nycmathguy

    nycmathguy

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    Finally got a reply from Jenn's staff.

    Screenshot_20220508-163305_Gmail.jpg
     
    nycmathguy, May 8, 2022
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  5. nycmathguy

    MathLover1

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    it was about time
     
    MathLover1, May 8, 2022
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  6. nycmathguy

    nycmathguy

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    Check your PM.
     
    nycmathguy, May 8, 2022
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    MathLover1 likes this.
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