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Homework Help: Line integral question

  1. Jul 26, 2005 #1
    Calculate the line integral of the function v=(y的平方, 2x(y+1), 0) from the
    point a=(1,0,0) to the point b=(2,2,0)
    The correct Ans: 11

    However, when I was calculuating the problem,
    I supposed(is that the right word?) to make the parameter equations,

    x=1+t
    y=1+t
    z=0
    where 0<t<1
    but when I integrated the function, the answer is 6.
     
  2. jcsd
  3. Jul 26, 2005 #2
    i don't know why, but i see your function as some chinese characters, can you retype it in some other way:).
     
  4. Jul 26, 2005 #3

    TD

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    Homework Helper

    Are you sure about that parametrization of your path?

    I'd say

    [tex]\left\{ \begin{array}{l}
    x = t \\
    y = 2t - 2 \\
    z = 0 \\
    \end{array} \right[/tex]

    or

    [tex]\left\{ \begin{array}{l}
    x = t + 1 \\
    y = 2t \\
    z = 0 \\
    \end{array} \right[/tex]
     
  5. Jul 26, 2005 #4

    HallsofIvy

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    Science Advisor

    when t= 0, your parametrization gives (1, 1, 0), there is no value of t that gives (1, 0, 0).
     
  6. Jul 27, 2005 #5
    sorry, i mistyped~
    a=(1,0,0)
     
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