What is the vector orthogonal to <-3,2,0> and <0,2,2> with the form <1,_,_>?

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To find a vector orthogonal to <-3,2,0> and <0,2,2> in the form <1,_,_>, the cross product method was initially attempted but led to an incorrect result. The correct calculation revealed a vector <2,3,6>, which does not fit the required format. It was suggested that dividing the components by 2 would yield a valid solution, resulting in the vector <1.0, 1.5, 3.0>. The discussion clarified that the uniqueness of the orthogonal vector allows for scalar multiplication, confirming that there is no requirement for integer components. Ultimately, dividing by 2 provided the correct answer, resolving the initial confusion.
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Find a vector orthogonal to both <-3,2,0> and to <0,2,2> of the form
<1,_,_> (suppose to fill in the blanks)

well i thought the cross product would do the trick, but i keep getting the wrong answer.
I|2 0| - j |-3 0| + k |-3 2|
|2 2| |0 2| |0 2|

(format is kinda messed up, but I am pretty sure you can tell how i had it set up)

i(4-0) -j(-6-0)+ k(-6-0) = 4i+6j+6k = 2i+3j+6k


so the answer should be <2,3,6> which is obviously incorrectly cause i don't even have a 1.
 
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Whatupdoc said:
Find a vector orthogonal to both <-3,2,0> and to <0,2,2> of the form
<1,_,_> (suppose to fill in the blanks)

well i thought the cross product would do the trick, but i keep getting the wrong answer.
I|2 0| - j |-3 0| + k |-3 2|
|2 2| |0 2| |0 2|

(format is kinda messed up, but I am pretty sure you can tell how i had it set up)

i(4-0) -j(-6-0)+ k(-6-0) = 4i+6j+6k = 2i+3j+6k


so the answer should be <2,3,6> which is obviously incorrectly cause i don't even have a 1.

assuming that's the correct answer, why don't you multiply by a scalar
 
Whatupdoc said:
Find a vector orthogonal to both <-3,2,0> and to <0,2,2> of the form
<1,_,_> (suppose to fill in the blanks)

well i thought the cross product would do the trick, but i keep getting the wrong answer.
I|2 0| - j |-3 0| + k |-3 2|
|2 2| |0 2| |0 2|

(format is kinda messed up, but I am pretty sure you can tell how i had it set up)

i(4-0) -j(-6-0)+ k(-6-0) = 4i+6j+6k = 2i+3j+6k


so the answer should be <2,3,6> which is obviously incorrectly cause i don't even have a 1.

You're pretty much right, apart from the sloppy sign change that crept in towards the end for no reason (-6k not +6k). Is it specified in the question that all components must be integers? If not, I would suggest simply dividing your answer by 2.
 
Theoretician said:
You're pretty much right, apart from the sloppy sign change that crept in towards the end for no reason (-6k not +6k). Is it specified in the question that all components must be integers? If not, I would suggest simply dividing your answer by 2.
It can't be specified that the components are all integers because there is only one unique vector that is perpendicular to two non-colinear vectors, up to constant multiples. So dividing gives the unique answer to the problem.
 
LeonhardEuler said:
It can't be specified that the components are all integers because there is only one unique vector that is perpendicular to two non-colinear vectors, up to constant multiples. So dividing gives the unique answer to the problem.

I suppose that I was being over cautious that I could have made some kind of mistake or overlooked something but you are right of course.
 
thanks alot, dividing by 2 worked. i had the -6 in on my paper, but when i typed it on here, everything was messed up including the answer i gave at the end. i was really sleepy awhile i was typing it, thanks agian for the help
 
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