## anonymous 5 years ago how do i do vectors? dont get it...

1. anonymous

Vectors are merely a representation of each coordinate in a basis direction. So for example giving directions. You could say up 2 miles, left 3 miles, and the vector would be (3,2) (assuming x,y configuration). So in x,y,z 3-space it is $r = (x,y,z)$ or $r = xi + yj + zk$. So say a vectors travels right 2 units, up 3 units, and forward 4 units, the vector r is : $r = (2, 3, 4)$

2. anonymous

by doing this you can then add vectors quite simply by merely adding their respective components. $r = (2,3,4)$ and $v = (1, -3, 6)$$r+v = (2+1, 3-3, 4+6) = (3, 0, 10)$

3. anonymous

awwww thankyou so much :)

4. anonymous

also, one thing, don't confuse vectors with coordinates(ie points) a vector has a length and a direction. a point is just a location in space. So for example I could place a vector $v = (2,2,2)$on a point $P(1,1,1)$ and this vector would if I were to say follow it, would then point to the point say $Q(1+2,1+2,1+2) = Q(3,3,3)$ so remeber that a vector is NOT a point, it describes both a direction and a magnitude. BTW the magnitude of a vectore is : $|v| = \sqrt(2^2 + 2^2 + 2^2 ) = \sqrt(12) = 2\sqrt(2)$ this is the magnitude or "norm" of a vector

5. anonymous

$**2\sqrt(3)$