Question

If c = a * b what can be said about c . a and c . b? (All of the letters have arrows over them)

PLEASE HELP! Thanks :)

Answer 1

arrows tend to be notation for vectors; which means the * would be read as a dot product

Answer 2

Ok

Answer 3

This is a vectors question by the way

Answer 4

a dot product creates a scalar, not a vector tho

Answer 5

Ok

Answer 6

that would tell me that:\[\vec c = \vec a * \vec b\] is not a proper construct to me

Answer 7

c would have to be a number, not a vector for this to indicate a dot product

Answer 8

\[\vec c = \vec a \times \vec b\] is doable to me, it would be a cross product

Answer 9

I edited the question, thats how it is exactly

Answer 10

so it has the "x" :)

Answer 11

no, it has a star and 2 periods

Answer 12

im not sure if that is read as sarcasm or not .....

Answer 13

lol im not being sarcastic at all

Answer 14

hmm, a star with 2 periods .... i got no idea what that notation would suggest then

Answer 15

Noo lol, in the question I posted, the first part has a star but the other two parts both have periods in between them... do you get it?

Answer 16

i see that, im just not sure what to make of it.

Answer 17

hmm... should I skip it then?

Answer 18

is there a "help solve" option beside it? or can you take a screen shot if this is question is on a computer screen?

Answer 19

Ok, ill take a picture hold on

Answer 20

Its number 3b

Answer 21

the notation used for this is not standard by any means - the person who write it up used their own notation. In order to determine what they are trying to express, we would need to know what their notation is meant to convey in terms of the more conventional usages.

Answer 22

i can take a guess and say * means x; and . means a dot product ....

Answer 23

then it kinda makes sense to me

Answer 24

Ok, yea

Answer 25

axb produces a vector that is perp to both a and b

therefore, the dotproduct of perp vectors = 0

if c = axb, then c.b = 0 and c.a = 0

Answer 26

IS that it :O?

Answer 27

thats the best i can make of it ...

Answer 28

if c = a cross b; then c dot a and c dot b are equal to 0 since c is perp to a and b both

Answer 29

I see

Answer 30

So should I write it just as you have " if c = a cross b; then c dot a and c dot b are equal to 0 since c is perp to a and b both"?

Answer 31

..... i would, unless you have your own way of expressing it :)

Answer 32

Nope :P THANKS! I was stuck on this one foreverr

Answer 33

:)

Answer 34

good luck :)