Hi there, i'm a bit stuck on this question:(adsbygoogle = window.adsbygoogle || []).push({});

" Given 3 non-coplanar vectors a, b and c convince yourself that the position vector r of any point in space may be represented by

r = λa + μb + γc

for some real numbers λ, μ and γ.

Show that

r.(bxc) = λa.(bxc) ,

r.(axb) = γa.(bxc) ,

r.(cxa) = μa.(bxc) . "

I understand how they get the first one - the cross product of b and c is perpendicular to both of them, so won't contain any b or c components. Hence when you do the dot product you'll be multiplying the b and c bits of r by zero so they disappear. However I don't get the other two...?

Please help!

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# Homework Help: Vector question

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