Given: u <-1, 7> and v <4, -3> What is the measure of the angle between them?
u • v = |u| |v|cosØ, where Ø is the angle between them
-4 -21 = √50 √25 cosØ
-25 = 25√2cosØ
cosØ = -1/√2
Ø = 135°
-4 -21 = √50 √25 cosØ
-25 = 25√2cosØ
cosØ = -1/√2
Ø = 135°