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Tangent vector

  1. Aug 6, 2010 #1
    1. The problem statement, all variables and given/known data

    Show that the curve
    has exactly one self-intersection point and finnd the two unit tangent vectors (in the direction of increasing t) at this point.

    I have found the self intersection. I know that a unit tangent vector is the derivative of each component>But the wording has me a bit confused.What does it mean "in the direction of increasing t at this point"?

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Aug 6, 2010 #2
    A tangent line to the curve extends in both directions (it has arrows on both ends).
    In contrast, a vector extends in a single direction (only its head has an arrow).

    You need to find the unit tangent in the direction of increasing t, not the opposite. Understand?
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