Question

SO HARD OMG! unit vector cross product help plzz
http://puu.sh/4swkm.png

Answer 1

@agent0smith

Answer 2

what is \[\hat{c}\]?

Answer 3

it's axb?

Answer 4

\[\hat{a}\times\hat{b}=\overset{\rightarrow}{c}\]

Answer 5

yes, but how to prove c vector equals to c unit vector??

Answer 6

HOW???

Answer 7

If a and b are perpendicular, then the magnitude of a x b is just the magnitude of a times the magnitude of b.

Answer 8

true, but they C is not the magnitude of a x b

Answer 9

You're asking why the magnitude of c is equal to 1, and I'm telling you that
\[ |\vec{c}| = |\vec{a} \times \vec{b} | = |\vec{a}| |\vec{b}| \]because a and b are perpendicular.

Answer 10

and obviously the magnitudes of a and b are equal to one.

Answer 11

my question is why c unit vector is equal to c vector, as stated in the question

Answer 12

You understand that a vector is a unit vector if its magnitude is one, right?

Answer 13

yes

Answer 14

and you now understand that the magnitude of the vector c is one?

Answer 15

no

Answer 16

Okay, well I cannot possibly explain it more clearly than I did above, so take a look at that again.

Answer 17

If a and b are perpendicular, then the magnitude of a x b is just the magnitude of a times the magnitude of b.

Answer 18

that is correct.

Answer 19

how you know that's correct

Answer 20

Because |a x b| = |a| |b| sin(theta) where theta is the angle between them. If they are perpendicular, theta is 90 degrees, which means sin(theta) is one.

Answer 21

or can i just say that |a x b| yields a square of side 1

Answer 22

yields the area of a square of side 1*

Answer 23

hey are you a university student? you are really good in math!

Answer 24

I mean, if you're referring to the fact that the magnitude of a cross product is equal to the area of the parallelogram defined by its vectors, and if the vectors are perpendicular that parallelogram is a rectangle, and if the magnitude of the vectors are both equal to one than it's a square............... sure if you want, or you could just simply say what I did above. Up to you. And no, I not an undergraduate anymore, I am in graduate school.

Answer 25

ok thx <3 u

Answer 26

in the most heterosexual way possible ;)