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Homework Help: A to a+dx

  1. Feb 13, 2012 #1
    1. The problem statement, all variables and given/known data
    The function f changes value when x changes from a to a+dx. Find the true change and estimated change.
    f(x)=x2-x, a=3, dx=.04

    a) .2;.08 b).2016;.2016 c).2016;.2 d).2016;.08

    2. Relevant equations



    3. The attempt at a solution
    dy=(2x-1)dx
    dy=.2
    Answer = C, but idk what the first number is.

    IDK what to do with that tho lol.
     
  2. jcsd
  3. Feb 13, 2012 #2

    eumyang

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    Homework Helper

    The first number you get from
    f(a + dx) - f(a),
    it looks like.
     
  4. Feb 13, 2012 #3
    Nope I tried that, I end up getting .2416 for some reason >.<
     
  5. Feb 13, 2012 #4

    eumyang

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    Homework Helper

    Try again. Find
    f(3.04) - f(3).
     
  6. Feb 13, 2012 #5
    Lol what a fail, I was doing (3.04)2-3 not 3.04..

    Thanks, kind of embarrassing.
     
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