- #1

- 191

- 0

## Homework Statement

There are two points p1 pointing up p2 pointing right

## Homework Equations

## The Attempt at a Solution

I need to find [tex]\stackrel{\rightarrow}{p1}[/tex] * r^

[tex]\stackrel{\rightarrow}{p2}[/tex] X p1^

[tex]\stackrel{\rightarrow}{p2}[/tex]* r^

they got [tex]\stackrel{->}{p1}[/tex] * r^ =0 why is that? i know if they are perpendicual than they =0 but not sure where r^ is pointing

[tex]\stackrel{->}{p2}[/tex] X p1^ =p

^{2}well i know when 2 vectors are paralle the = 0 so i am guess when they are perpendicular they are p

^{2}, but only one is a vector not sure if that matters.

[tex]\stackrel{->}{p2}[/tex]* r^ = p well i am guessing from this, that r^ is parallel with p2. thats why with p1 its 0, its perpendicular, but how do we find out which way r^ is pointing?

thxs