Vector subtraction - v – u =
Vector multiplication – kv = k
To find a vector from 2 points do P2 – P1
Vector equation - (x, y) = (x˳, y˳) + t(a, b)
Parametric equations:
x = x˳ + at
y = y˳ + bt
-|u| = sqrt x^2 + y^2 ---> magnitude of a vector
Ex 1. Given A(4, 2) and B(9, -1), express AB in a compund
form and find |AB|
(9, -1) – (4, 2) = <5, -3>
|AB| = sqrt 5^2 + (-3)^2 = sqrt 25 + 9 = sqrt 34
Ex 2. A force of 2N is represented by an angle of 145 degrees
with the x axis. Find its components.
x/2 = cos145 y/2 = cos145
x = 2cos145 = -1.638 y = 2cos145 = 1.147
<-1.638, 1.147>
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