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Plane Curve

  1. Jul 1, 2007 #1
    Sketch the plane curve in the xy-plane and find its length over the given interval:
    r(t) = (6t-3)i + (8t+1)j on [0,3]

    Here's what I've got so far:
    r'(t) = 6i + 8j
    llr'(t)ll = sqrt of 6^2+8^2 = 10
    s = integral 0-3 10dt
    = 10x ]0 to 3
    = [30-0]
    = 30

    I just need help on how to sketch this plane curve. Thanks.
    Last edited: Jul 1, 2007
  2. jcsd
  3. Jul 2, 2007 #2


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    to sketch curves, you can only find the derivative to get an idea of how the curve behave and then just calculate a bunch of points and link them together. it's tedious and boring, just hang on.
  4. Jul 2, 2007 #3


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    Since the functions for the x and y components are linear, this is, of course, a straight line! Find the point corresponding to t= 0, the point correponding to t= 3 and draw the straight line between them.
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