How do you find the unit vector that has the same direction as the vector from the point A= (5, 2) to the point B= (3, 2)?

1 Answer
Jan 7, 2017

((-1),(0))=-hatveci

Explanation:

if A has coordinate (5,2) then its position vector is given by

vec(OA)=5hatveci+2hatvecj=((5),(2))

if B has coordinate (3,2) then its position vector is given by

vec(OB)=3hatveci+2hatvecj=((3),(2))

The vector from A toB is:

vec(AB)=vec(AO)+vec(OB)

vec(AB)=-vec(OA)+vec(OB)

vec(AB)=-((5),(2))+((3),(2))

vec(AB)=((-5+3),(-2+2))=((-2),(0))

call this vector vecd

A unit vector in this direction is given by

hatvecd=(vec(d))/|vecd|

vecd=((-2),(0))=>|vecd|=2

hatvecd=1/2((-2),(0))=((-1),(0))