Let v1 = (-6,4) and v2 = (-3, 6). Compute the following:
c. The scalar projection of v1 onto v2
d. The projection of v1 onto v2
Try not to give me the answer

Question

Let v1 = (-6,4) and v2 = (-3, 6). Compute the following:
c. The scalar projection of v1 onto v2
d. The projection of v1 onto v2
Try not to give me the answer

anonymous · Answer

just use the formulas

anonymous · Answer

you should a formula for the prjection of v1 onto v2

anonymous · Answer

What is the formula, that is what I don't really get.

anonymous · Answer

do you know what dot product and cross product are?

anonymous · Answer

@Eureka70  What is the cross product?
This is the dot product (x1,y1)*(x2,y2)

anonymous · Answer

cross product is more complicated multiplication somewhat like dot product, but in this case you don't need it in this case. the projection of one vector onto another is the dot product and gives a scalar.  that should be what you need for number 1. For number i think it wants the part of the vector 1 that is in the direction of v2, which is easy to find.

the scalar projection should have given you (technically) a value that we use as a coefficient. now if we take this scalar divided by the total length of v2, should give us the fraction of v2 that the projection of v1 covers. so if we multiply this fraction by v2, we should get the projection of v1 on v2.