The definition of average velocity is:

According to this definition, the vector average velocity is obtained by dividing a vector by a scalar.� Since the scalar () is always positive, this definition implies that the two vectors (�and ) have the same direction.� We would like to apply this definition to find the velocity at point D.� Then �and �in the definition correspond to an interval that spans point D, i.e., with an initial point just before point D and with a final point just after point D.

You indicated that the velocity of the object at point D is in direction 8.� This means that the displacement vector in the definition above for the interval that spans point D also points in direction 8.� Recall that the displacement for an interval is the vector whose tail is at the initial location and whose head is at the final location of the interval.� The interval that spans point D has an initial location just prior to point D and a final location just after D.� Does the displacement vector from the initial point to the final point really point in direction 8?

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