Position Vectors; Displacement vector as vector subtraction of position vectors; Magnitude of displacement, direction of displacement as unit vector; Average Velocity vector as scalar division of displacement vector by time taken in the displacement; show that the unit vector of displacement and average velocity are equal to each other; fundamental principle of vector physics: mutually perpendicular vectors do not interfere with each other- you change one even by a large value, it has no effect on its vector sibling perpendicular to it!
