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

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    Orthogonal Vector
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Homework Help Overview

The discussion revolves around finding a vector that is orthogonal to the vectors <-3,2,0> and <0,2,2>, specifically in the form <1,_,_>. Participants explore the use of the cross product to determine this vector.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the application of the cross product and express concerns about obtaining the correct form of the answer. There is a suggestion to consider scalar multiplication to achieve the desired format.

Discussion Status

Some participants have provided guidance on correcting sign errors and the possibility of dividing the resulting vector to fit the required form. There is acknowledgment of the uniqueness of the orthogonal vector up to scalar multiples, indicating a productive exploration of the problem.

Contextual Notes

Participants question whether the components of the vector must be integers and discuss the implications of this on the solution. There is a mention of potential mistakes in calculations due to formatting issues in the discussion.

Whatupdoc
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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 a lot, 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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