Question

Let v1 = (-6,4) and v2 = (-3, 6). how to find the scalar projection of v1 onto v2?

Answer 1

\[proj_{V _{2}}V _{1}=\frac{ V _{1}.V _{2} }{ V _{2} . V _{2}}V _{2}\]

Answer 2

So that is the dot product of v1 and v2 divided by v2 dotted with v2...
all times v2

Answer 3

Do you know dot products?

Answer 4

not exactly but i can try with the information you gave me.

Answer 5

The scalar (or component) of v1 onto v2 is

comp_v1(v2) = v1∙v2/||v1|| = (-6(-3) + (4)(6))/√((-6)²+(4)²) = 5.82

Answer 6

\[(a,b).(c,d)=ac+bd\] you multiply corresponding entries and then add up those products.

Answer 7

thanks. (: mind helping with one last question related to this problem?

Answer 8

not scalar projection but Just the projection of v1 onto v2

Answer 9

The projection of v1 onto v2 is simply the scalar component times a unit vector in the direction of v1.

proj_v1(v2) = v1∙v2/||v1||² v1 = (14/15)(-6,4) = (-28/5, 56/15)

Answer 10

Actually I should have read THIS problem better.
The SCALAR projection is what I said but without the multiplication by v2.

What I described is projection (aka vector projection)

Answer 11

What Nurali put is the scalar projection.

Answer 12

okay, I see. thanks for all the help(:

Answer 13

The projection of v1 onto v2 is simply the scalar component times a unit vector in the direction of v1.

proj_v1(v2) = v1∙v2/||v1||² v1 = (21/26)(-6,4) = (-63/13, 42/13)

Answer 14

My Pleasure.