It isn't an uncommon question, and I still encounter such queries from time to time. Since one of my students asked about this very recently, I thought it opportune to share a personally crafted set of explanations on my supplementary website:
http://www.a-levelmaths.com/apps/blog/s ... ot-product
Hope you will find it useful. Peace.
Vectors: Length of projection-cross or dot product
Is there life after O/A-Levels? Definitely! How well a person does in tertiary education is correlated with job opportunities open to the person. Discuss issues pertaining to nstitutes of higher learning here.