Find the projection of u onto v. Then write u as the sum of two orthogonal vectors, one being projvu
u=8,4 and v = 2,-4
I attempted to write the projection and came up with 0,0, how do i move on from that???.

Question

Find the projection of u onto v. Then write u as the sum of two orthogonal vectors, one being projvu
u=8,4 and v = 2,-4
I attempted to write the projection and came up with 0,0, how do i move on from that???.

amistre64 · Answer

we need to unit vector for v

then scale it by the cos of the angle between them

amistre64 · Answer

your going to have some:  n<2,-4>  such that n is a scalar to fit

anonymous · Answer

How would i do that? they are perpendicular

amistre64 · Answer

|dw:1411947521453:dw|

amistre64 · Answer

16-16, yeah, the they appear to be perp eh

amistre64 · Answer

then the length of projection u on v is 0

anonymous · Answer

Yep, which makes me really confused on how to find a vector at a right angle to something of length zero.

amistre64 · Answer

proj u on v = <0,0>

anonymous · Answer

Ok, and i need " the sum of two vectors at right angles to eachother, one of them being  0,0"

anonymous · Answer

would the other  be 0,0, making the sum 0,0?

amistre64 · Answer

the other would be u assuming that we are reading this right

anonymous · Answer

The question

anonymous · Answer

Really? why

amistre64 · Answer

|dw:1411947830536:dw|

anonymous · Answer

Possible answers: <8,4> <2,- 4> <4,2> none of these

amistre64 · Answer

8, 4 2,-4 ----- 16-16 = 0 proj u on v = 0 <8,4>/sqrt(80) = <0,0>

anonymous · Answer

So the answer would be a?

amistre64 · Answer

thats what im thinking yes

anonymous · Answer

ok:)

amistre64 · Answer

spose we have u = 0,1  and v = 1,0

u = 0v + 1u