Vector Formulae

Question 1

Scalar Product

Answer 1

a.b = |a||b|cos θ

Question 2

Vector Product

Answer 2

WHAT IS IT USED FOR???

Question 3

Acute angle θ between 2 intersecting lines

Answer 3

cos θ = |(a.b) / (|a||b|)|
a and b = DIRECTION vectors

Question 4

Acute angle θ between a line and plane

Answer 4

sin θ = |(b.n) / (|b||n|)|
L1: r = a + λb Π1: r.n = k

Question 5

Acute angle θ between two planes

Answer 5

cos θ = | (n1.n2) / (|n1||n2|)|
n1 and n2 = NORMAL vectors

Question 6

Vector Projection