Question

I don't remember being more angry at a question before. I **REALLY** need help with this URGENTLY.
vector AB multiplied by vector BC = 0. AB is given as (3 (above) 4) information and BC is not given. What does this information give us? How can I find BC? Thanks in advance.

Answer 1

wouldn't the vector be 0 on the top and 0

Answer 2

what does (3 (above) 4) mean? can u represent it in better way,maybe by drawing?

Answer 3

\[\left(\begin{matrix}3 \\ 4\end{matrix}\right)\]

Answer 4

Looking back at my book I see a theorem that says that the result scalar would b zero if and only if you multiply it by a zero vector

Answer 5

it is not possible for BC to be no line at all. it has to have some magnitude. (3 (above 4)) <- in brackets as i showed above --- multiplied by this BC equals to 0. I don't know if the dot in the middle between AB and BC like AB(dot)BC means a specific kind of multiplification like dot product I heard about, but that's all I know.

Answer 6

okk,so 3 above 4 tells u that AB has 2 components with magnitude os 3 and 4 of each component
AB dot BC = 0 tells you that these two vectors are perpendicular to each other
but only this much info is not sufficient to find BC vector.

Answer 7

Well if we set it up in the case were we find the transpose of the first vector then it clearly shows that in order for it to be zero we need a zero vector. Or we can simply trial an error a couple of numbers that we want in order to make the outcome zero. Basically there are infinite number of solutions

Answer 8

the perpendicularity was all I needed, thanks! I had some other info from the long-ish exercise of which just a part i gave to yo.