Question

Find the unit vector in the direction of u=(-3,2). Write your answer as a linear combination of the standard unit vectors i and j.
a. u=-3[sqrt(13)/13]i+2[sqrt(13)/13]j
b. u=-3[sqrt(5)/5]i+2[sqrt(5)/5]j
c. u=3[sqrt(5)/5]i-2[sqrt(5)/5]j
d. u=3[sqrt(13)/13]i+2[sqrt(13)/13]j

I do not understand this. Can someone please explain it to me?

Answer 1

|u| = √(9+4) = √13
So, divide u by its length to get a unit vector (length=1)

so, (a)

If you've advanced to the point where you're studying vectors, your teacher should stop insisting on rational denominators. I much prefer 1/√13 to the cumbersome √13/13

just sayin' ...

Answer 2

Hey is there any way that we could talk one on one? Im pretty sure were im the same math class as you and want some help pls!! :))