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

If A = (2,-2,1) and B = (2, 0, -1)

show by explicit calculation that

i) A^B is orthogonal to A

ii) (A^B)^B lies in the same plane as A and B by expressing it as a linear combination of A and B

2. Relevant equations

A^B = |A||B|sin θ

3. The attempt at a solution

I know that when you do the cross product of two vectors the result will be a vector that is perpendicular to both and I can draw a diagram to demonstrate. However I can't show it by explicit calculation. :(

I thought maybe if I could prove that the angle between them was ∏/2...

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# How do I prove that A^B is orthogonal to A?

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