CSE 167 Lecture 2: L2 1/10/19

• School: UCSD
• Department: Computer Science and Engineering
• Course: CSE 167
• Professor: Ravi Ramamoorthi

Document Summary

Commutative! a + b = b + a. X and y can be any (usually orthogonal unit) vectors. Sum vectors using their x and y coordinates (xa + xb, ya + yb) Use rhr (right hand rule) to associate the x, y, and z axes. Dot (scalar) product a b = ||a|| ||b|| cos . Length of vector b along the direction of a (aka projection of b onto a) = (xaxb) x x + (yayb) y y + (xayb) x y + (yaxb) y x. A = ||b a|| x (a / ||a||) = (a b) a / ||a||2. Note: a (b + c) = a b + a c. Dot product in cartesian components a b = xaxb + yayb (why?) a = xa x + ya y. B = xb x + yb y a b = (xa x + ya y) (xb x + yb y)