Khan Academy
Khan Academy: Components of Vectors and Endpoints
Find the components of a vector. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
CK-12 Foundation
Ck 12: Unit Vectors and Components
[Free Registration/Login may be required to access all resource tools.] Here you'll learn how to break down a vector into component vectors and unit vectors.
CK-12 Foundation
Ck 12: Unit Vectors and Components
[Free Registration/Login may be required to access all resource tools.] A collection of learning resources to help students understand how to find the components of a vector by subtracting the coordinates of an initial point from the...
Wolfram Research
Wolfram Math World: Vector Difference
This site defines vector difference. Includes a formula and links to related topics.