Khan Academy
Khan Academy: Unit Vectors
Find a unit vector in the direction of a given vector. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
CK-12 Foundation
Ck 12: Trigonometry: Resultant as Magnitude and Direction
[Free Registration/Login may be required to access all resource tools.] Express vectors in magnitude and direction form.
Wolfram Research
Wolfram Math World: Parallel Vectors
Math World site offers a method of determining if two vectors are parallel based on their cross product.
National Council of Teachers of Mathematics
The Math Forum: Unit Vectors and Unit Circle
Description of the unit vector and its relationship to the unit circle.
National Council of Teachers of Mathematics
The Math Forum: Vector Addition: Geometry
Illustrates and describes how to add two vectors graphically.
National Council of Teachers of Mathematics
The Math Forum: Definition of the Dot Product
Definition of dot product and an application.
National Council of Teachers of Mathematics
The Math Forum: Dot Products of Non Unit Vectors
Description of finding the formula for the dot product of any two vectors.
Wolfram Research
Wolfram Math World: Perpendicular Vectors
Come to this site to find the transformational matrix to find the vector rotated 90 degrees from the original. The site also states the special relationship between two perpendicular vectors when using the dot product.