This is about vectors

Question

anonymous · Answer

@amistre64

anonymous · Answer

I'm not familiar with the notation. What does the down arrow between vectors represents? Cross product?

anonymous · Answer

its represents the projection of u onto v

anonymous · Answer

Wouldn't #3 imply that u and v are orthogonal or they are the same?

anonymous · Answer

whats orthogonal

isaiah.feynman · Answer

Orthogonal means they are perpendicular.

abb0t · Answer

Just a fancy word for saying perpendicular, as the person has said above.

anonymous · Answer

oh okay so then number three implies they are equal

isaiah.feynman · Answer

Can you draw number three, because I don't know what "projection of v to u" means

anonymous · Answer

well thats the part on what i don't know how to do

isaiah.feynman · Answer

Never heard of projection of one vector to another.

isaiah.feynman · Answer

Number 3 I'd say no.

anonymous · Answer

sorry what do you mean no?

isaiah.feynman · Answer

They are not equal

anonymous · Answer

ohh actually all of those are equal .. its just i have to prove they are equal

anonymous · Answer

@ganeshie8

ganeshie8 · Answer

#3 or #4 ?

phi · Answer

The projection of vector u onto vector v  will be a vector
It will point in the same direction as vector v
it will have a length  | u | cos A  where A is the angle between the two vectors
|dw:1385558127501:dw|

if we call "v hat" the vector v normalized to unit length, we can say
$$ u \downarrow v = \left(|u|\ \cos A\right) \hat{v}$$