1. The notion that I forgot to do is the notion of a unit vector.

2. In fact, that would be true if the coefficients here formed a unit vector.

3. And in our notation, i, the unit vector i that you learned in physics class, would be the vector 1, 0.

4. Same as the tangent indicatrix except that the unit vector t moves in conjunction with (parallel to) the Binormal instead of the unit tangent

5. The Curl of a vector field F, denoted by Curl F, or ∇ × F, or rot F, at a point is defined in terms of its projection onto various lines through the point.If ^ is any unit vector, the projection of the Curl of F onto ^ is defined to be the limiting value of a closed line integral in a plane orthogonal to ^ divided by the area enclosed, as the path of integration is contracted around the point.