Use Graph to Find Delta...1

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

  1. nycmathguy

    nycmathguy

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    Calculus
    Section 2.4

    Can you work out 5 as a guide for me to do 6 on my own? Jenn does not teach how to do this in her video lessons.

    Screenshot_20220507-174020_Samsung Notes.jpg
     
    nycmathguy, May 7, 2022
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  2. nycmathguy

    MathLover1

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    5.
    use the graph to find delta if |x-2|<δ then |sqrt(x^2+5)-3|<0.3

    The function is y=sqrt(x^2+5)

    find delta if |x-2|<δ whenever |sqrt(x^2+5)-3|<0.3

    We need to establish a connection between |x-2|<δ and |sqrt(x^2+5)-3|<0.3

    Consider |sqrt(x^2+5)-3|<0.3

    Solve the inequality.

    -0.3< |sqrt(x^2+5)-3|<0.3

    -2.42693<x<-1.51327
    or
    1.51327<x<2.42693


    Since δ>0

    0< |x-2|<δ

    0< |x-2|<2.42693

    Compare the inequality above

    δ=2.42693
     
    MathLover1, May 8, 2022
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  3. nycmathguy

    nycmathguy

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    You learned this stuff long ago and still remember how to do it. Amazing.
     
    nycmathguy, May 8, 2022
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  4. nycmathguy

    MathLover1

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    I learned that 47 years ago.
     
    MathLover1, May 8, 2022
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  5. nycmathguy

    nycmathguy

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    I watched two samples of the epsilon-delta definition with Jenn today. I am still confused. Wow! How time flies!!! She struggled to break down the material. It was easy to see that for each problem. Mira, if I could cancel the membership, I would.
     
    nycmathguy, May 8, 2022
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  6. nycmathguy

    nycmathguy

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    Mira,

    Here is your chance to contact Tom at the website:

    Screenshot_20220508-170413_Gmail.jpg

    Maybe you have some questions for him about Jenn and her website. I will now text my reply to Tom. Check your PM.
     
    nycmathguy, May 8, 2022
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