(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Prove that If [tex]\vec{a}[/tex]x [tex]\vec{b}[/tex] = 0, then [tex]\vec{a}[/tex]is parallel to [tex]\vec{b}[/tex].

2. Relevant equations

3. The attempt at a solution

I tried attempting the solution by using the following:

[tex]\vec{a}[/tex] = [a_{1}, a_{2}, a_{3}]

[tex]\vec{b}[/tex] = [b_{1}, b_{2}, b_{3}]

When I took the cross product of a x b I got::

[a_{2}b_{3}- b_{2}a_{3}a_{3}b_{1}- b_{3}a_{1}, a_{1}b_{2}- b_{1}a_{2}]

and we can make this equal to 0, but I am confused here; I have no idea on how to prove that when a x b is 0, vectors a and b are parallel.

any help is appreciated!

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# Homework Help: Cross product question

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